Remotely controlled vertical takeoff and landing aircraft
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- XMOBOTS AEROESPACIAL E DEFESA LTDA
- Filing Date
- 2026-01-23
- Publication Date
- 2026-08-06
Smart Images
Figure BR2026050022_06082026_PF_FP_ABST
Abstract
Description
"REMOTELY CONTROLLED AIRCRAFT WITH VERTICAL TAKEOFF AND LANDING"
[0001] The present invention relates to a remotely controlled aircraft with vertical takeoff and landing, particularly used for operations in agricultural fields, aerial photogrammetry and military applications, comprising a lightweight structural assembly with mixed components, an airflow measurement device resistant to water accumulation to withstand flights in adverse conditions, and a redundant recovery system. Description of the state of the art
[0002] Many types of remotely controlled aircraft, also known as unmanned aerial vehicles, have been developed for a wide variety of missions and uses, both in civilian and military settings.
[0003] These already known remotely controlled aircraft exhibit a wide variety of constructive configurations in relation to their structure, such as bicopters (with two rotors), tricopters (with three rotors), quadcopters (with four rotors), and a variety in the configurations adopted for propulsion, such as ducted engines, counter-rotating propellers, variable-pitch propellers, as well as propulsion by means of "tilt-rotors," that is, propulsion initially positioned facing downwards for vertical takeoff and landing (VTOL), but which at a certain point in the aircraft's flight rotates and assumes a different position.
[0004] With regard to wings, the designs of these aircraft also propose equally vast configurations with fixed wings, movable wings, folding wings that expand, flying wings, biplanes, multiplanes, or tandems. However, most remotely controlled aircraft comprise the more conventional configurations with well-defined divisions of wings, fuselage, and tail.
[0005] To exemplify the different types of wings in prior art aircraft, document US9789950 describes an aerial vehicle comprising a fuselage, foldable wings associated with the fuselage and configured to move between a retracted and expanded configuration, and a wing locking mechanism once the wings have been expanded. Document GB2490141 describes an unmanned aerial vehicle having a fuselage to which wings are attached. The fuselage is preferably made of Nylon using 3D printing and receives wing connections made by means of hinges so that the wings can be moved between an extended and a retracted position when necessary.
[0006] During the operation of a remotely controlled aircraft with vertical takeoff and landing, the moments of takeoff and landing tend to generate more vibration and stress on its structure, since the engines generate moment and force to overcome inertia and lift the aircraft off the ground, in addition to the stresses generated in fixed-wing flight, where the concentration of forces is on the wing instead of the structure. For these and other reasons, the overall structure of this aircraft needs to be reinforced to withstand all the stresses and still have a safety margin so that, throughout the entire flight envelope, the aircraft always operates in a safe region on the stress-strain curve of the material that makes up its structure. In this sense, various materials and compositions have already been used in the structure of these aircraft, from aeronautical aluminum to plywood.However, due to the necessary reinforcements required by the structure of this type of aircraft, the quantity and type of material used give these aircraft a high weight, affecting their flight range. With impaired flight range, the aircraft used for agriculture or aerial photogrammetry, for example, does not achieve satisfactory productivity.
[0007] Due to the vibrations generated during takeoff, landing, and flight, the structures of these aircraft are also reinforced to prevent these vibrations from interfering with the operation of the onboard sensors responsible for its control, such as the autopilot, altitude sensors, gyroscope, accelerometer, GPS, and communication systems. Any damage to the control and communication sensors jeopardizes the mission's success.
[0008] Document US8328130, for example, describes an unmanned aerial vehicle with vertical takeoff and landing capabilities and a structure or fuselage for that unmanned aerial vehicle. This document describes that the structure or fuselage is made by assembling tubes, and that this fuselage structure can be made of various materials, including composite materials that can be molded through injection molding, among others, in an attempt to reduce the weight of the aerial vehicle structure without compromising its strength and functionality.
[0009] Additionally, document US10017237 refers to unmanned aerial vehicle structures where the aerial vehicle structure is also tubular and made of plastic or composite material capable of providing structural rigidity to support the vehicle's components and maintain its integrity during flight operations. However, even though it is made using 3D printing and materials that tend to be lighter, the tubular structure is filled with a second material, such as carbon fiber, and this filling of the structure to aid in its rigidity results in an increase in the aircraft's weight and the aforementioned range problem.
[0010] Even though they are remotely controlled and unmanned aircraft, these aerial vehicles need to be able to operate in adverse conditions, such as rain, since they are used in missions that usually present unpredictable weather conditions, such as crop mapping. Therefore, devices like heaters, drain points, or redundant technologies are already widely used for this purpose; however, it is essential to have an appropriate pitot tube with a configuration resistant to wind changes to avoid erroneous readings by the aircraft controller and consequent deterioration in flight quality.
[0011] Finally, remotely controlled aircraft include recovery systems. These recovery systems for unmanned aircraft are diverse, ranging from forced landing routines for VTOL aircraft to the use of parachutes for fixed-wing aircraft, with the aim of safely recovering the aircraft in case of critical failures during flight. However, none of the known aircraft include redundancy for this system, that is, two recovery system options on the same aircraft for a safety backup in case of failure of one of the systems.
[0012] Therefore, even though several models of remotely controlled aircraft with different configurations and devices are already known, an aircraft with a lighter and more robust structure is needed, capable of operating safely in adverse weather conditions, especially in heavy rain scenarios, and equipped with redundant systems for its recovery in case of critical failures during flight. Objectives of the invention
[0013] Thus, the present invention aims to provide a remotely controlled aircraft with vertical takeoff and landing, comprising a robust and resistant structure, yet with reduced overall weight.
[0014] The present invention also aims to provide a remotely controlled aircraft comprising a rotor and wing configuration that allows for high flight autonomy.
[0015] Another objective of the present invention is to provide a remotely controlled aircraft, equipped with an airflow measurement device resistant to water accumulation, that allows it to perform a wide variety of missions, supporting flights in conditions of heavy rain.
[0016] It is also an objective of this invention to provide a remotely controlled aircraft comprising a redundant recovery system. Brief description of the invention
[0017] The present invention relates to a remotely controlled vertical takeoff and landing (VTOL) aircraft comprising (a) a main structure to which at least one and preferably four rotors are attached, the main structure being formed by a plurality of tubes connected to each other by means of joining elements that receive a fastening component, the main structure comprising (a.1) parallel reinforcement elements arranged to each other, each reinforcement element receiving a wing spar on which a wing is mounted and attached; and (a.2) a central body portion, disposed between the reinforcement elements, the central body portion comprising command and data processing modules and a redundant recovery system; and (b) an airflow measuring device comprising an inlet portion, an internal portion in which at least one drain orifice communicating with at least one flow channel is disposed, and a data reading portion linearly opposite to the inlet portion and associated with the central body portion of the main structure. Brief description of the drawings
[0018] Figure 1 - illustrates the remotely controlled aircraft, the subject of the present invention;
[0019] Figure 2 - is an exploded view of the remotely controlled aircraft that is the subject of this invention;
[0020] Figure 3 - is a perspective view of the main structure of the remotely controlled aircraft that is the subject of this invention;
[0021] Figure 4a - is a perspective view of a first variation of the joining element that makes up the main structure of the remotely controlled aircraft, object of the present invention;
[0022] Figure 4b - is a first schematic cross-sectional view of a second variation of the joining element that makes up the main structure of the remotely controlled aircraft, object of the present invention;
[0023] Figure 4c - is a second schematic cross-sectional view of a third variation of the joining element;
[0024] Figure 4d - is a schematic cross-sectional view of a fourth variation of the joining element;
[0025] Figure 5a - is a schematic, perspective view of the joining element associated with a component of the main structure of the remotely controlled aircraft, the subject of this invention;
[0026] Figure 5b - is a detailed front view of Figure 5a, illustrating the application of a fastening component to the joining element;
[0027] Figure 6 - is a perspective view of an airflow measurement device present in the remotely controlled aircraft, the subject of this invention;
[0028] Figure 7 - is a perspective and cross-sectional view of the airflow measuring device illustrated in Figure 6;
[0029] Figure 8 - is a perspective view of a variation of the payload device present in the remotely controlled aircraft, the subject of this invention;
[0030] Figure 9 - is a first schematic view of the redundant recovery system present in the remotely controlled aircraft, the subject of this invention; and
[0031] Figure 10 - is a second schematic view of the redundant recovery system present in the remotely controlled aircraft, the subject of this invention. Detailed description of the invention
[0032] According to a preferred embodiment and as can be seen in figures 1 to 10, the present invention relates to a remotely controlled aircraft 100 with vertical takeoff and landing (VTOL) and fully electric propulsion.
[0033] As can be seen in figure 1, in general terms the remotely controlled aircraft 100 comprises a main structure 50 to which at least one and preferably four rotors 30 are associated, a central body portion 54 flanked by wings 60 and an airflow measuring device 70 associated with the central body portion 54.
[0034] The main structure 50, illustrated in Figure 3, is formed by a plurality of tubes 51, 52, 53, all made of composite material, preferably carbon, and connected to each other by means of joining elements 20, so that the main structure comprises an “H” shaped arrangement to better distribute the stresses generated by vertical takeoff and landing operations on this main structure 50. In this case, the use of composite material, in this case carbon, is appropriate due to the high mechanical strength of this material combined with a low weight. This allows for an optimization of the weight of the aircraft 100 with adequate strength for the certification of the aircraft 100.
[0035] More specifically, the main structure 50 is formed by a first pair of linear structural tubes 51 comprising equal diameters and connected to each other by a joining element 20, and a second pair of linear structural tubes 51, comprising equal diameters and connected to each other by a joining element 20. The first pair of linear structural tubes 51 is arranged parallel and spaced apart from the second pair of linear structural tubes 51 so as to form a span 58. The first pair of linear structural tubes 51 is connected to the second pair of linear structural tubes 51 by a connecting tube 53, of smaller diameter than the linear structural tubes 51, fixed concurrently, preferably perpendicular, to the first and second pairs of linear structural tubes 51 also by joining elements 20.
[0036] As further illustrated in Figure 3, the main structure 50 comprises at least one and preferably four support tubes 52 which are associated with the first and second pairs of linear structural tubes 51 by means of joining elements 20. In this case, one pair of support tubes 52 is associated with the first pair of linear structural tubes 51 and another pair of support tubes 52 is associated with the second pair of linear structural tubes 51, forming a four-point landing support.
[0037] Reinforcing elements 59 are arranged in the connections of the connecting tube 53 with the first and second pairs of linear structural tubes 51. More specifically, one reinforcing element 59 is fixed to the first pair of linear structural tubes 51, externally in relation to the span 58 and next to the connection of this first pair of linear structural tubes 51 with one end of the connecting tube 53. Another reinforcing element 59 is fixed to the second pair of linear structural tubes 51, externally in relation to the span 58 and next to the connection of this second pair of linear structural tubes 51 with the other end of the connecting tube 53.The reinforcing elements 59 are flat, plate-like, made of carbon and have varying widths such that, when each reinforcing element 59 is fixed to the first and second pairs of linear structural tubes, the larger width is positioned near the connection points of the connecting tube 53 with the first and second pairs of linear structural tubes 51, since these are the connection points with high structural stress demands. The smaller width of the reinforcing element 59 is positioned near the connection of the support tube 52 with the first and second pairs of linear structural tubes 51.
[0038] At least one rotor 30 is associated with each end of the first pair of linear structural tubes 51 and the second pair of linear structural tubes 51, forming a quadcopter-configured aircraft with four rotors 30 for vertical takeoff and landing (VTOL). The rotors 30 comprise electric propulsion powered by at least one lithium-ion battery.
[0039] In addition to the rotors 30, the aircraft 100 comprises an auxiliary propeller 31 which is activated after vertical takeoff, to initiate cruise flight (in horizontal directions). The auxiliary propeller 31 is positioned in the gap 58 of the main structure 50, supported by auxiliary supports 55 formed by two pairs of carbon fiber tubes. Each pair of auxiliary supports 55 comprises the first ends associated with the auxiliary propeller 31 and the second ends fixed to the first and second pairs of linear structural tubes 51, by means of junction elements 20, and at the connection points with the connecting tube 53.
[0040] The joining element 20, as illustrated in figures 4a, 4b, 4c and 4d, is made of polyamide, preferably nylon PA12, and manufactured by additive manufacturing or 3D printing using MJF (Multi Jet Fusion) technology, which uses the fusion of powder layers to create the parts. The joining element 20 receives a fastening component 40.
[0041] For aircraft 100 there are four variations for the junction element 20; however, for all variations, this junction element 20 comprises a sleeve 21 that receives a portion or part of at least one linear structural tube 51 and / or a portion of a support tube 52 and / or a portion of a connecting tube 53 that will be fixed to another portion or part of at least one linear structural tube 51 and / or a portion of a support tube 52 and / or a portion of a connecting tube 53.
[0042] Therefore, in the first variation of the joining element 20 illustrated in figure 4a, the sleeve 21 is provided with a plurality of fixing holes 23 for joining a support tube 52 to a linear structural tube 51, the diameter of the support tube 52 being different from the diameter of the linear structural tube 51. In the second variation of the joining element 20 illustrated in figure 4b, the sleeve 21 is also provided with a plurality of fixing holes 23, however, the geometry of this variation of the joining element 20 allows it to join one linear structural tube 51 to another linear structural tube 51 of the same diameter.
[0043] In its third variation, illustrated in Figure 4c, the joining element 20 comprises a sleeve 21 having a plurality of fixing holes 23 and a plurality of fixing channels 231 arranged in a spiral, which are exposed on the inner surface of the sleeve 21 and in direct contact with the surface of the carbon tube that is inserted into the sleeve 21. Specifically in this case, the third variation of the joining element 20 is used for joining rotors 30 with linear structural tubes 51 and, because this is a joint subjected to torsional forces, the plurality of fixing channels 231 provides better chemical anchoring, as will be described below.
[0044] In the fourth variation of the joining element 20 illustrated in figure 4d, the sleeve 21 is provided with a plurality of fastening holes 23 and a plurality of fastening channels 231 arranged parallel to each other and exposed on the inner surface of the sleeve 21 and in direct contact with the surface of the carbon tube that is inserted into the sleeve 21. This fourth variation is used to join linear structural tubes 51 with other structural components of the aircraft 100, such as the wing spar 61 which will be described in detail later. The fastening channels 231 are preferably cylindrical and may be arranged in the sleeve 21 in a spiral shape (figure 4c) or parallel to each other (figure 4d).
[0045] The junction element 20 further comprises an inlet channel 22 communicating with the plurality of fastening channels 231 and with the plurality of fastening holes 23 and an outlet channel 24, diametrically opposite to the inlet channel 22 and also communicating with the plurality of fastening channels 231 and with the plurality of fastening holes 23.
[0046] Thus, as illustrated in figures 5a and 5b, the sleeve 21 receives the fastening component 40 through the inlet channel 22, the fastening component 40 is guided by a main channel 25, fills the plurality of fastening holes 23 and travels through and fills the plurality of fastening channels 231, making contact with a portion of at least one linear structural tube 51 and / or a portion of a support tube 52 and / or a portion of a connecting tube 53 disposed in the sleeve 21. The fastening holes 23 and the fastening channels 231 have the function of distributing the fastening component 40 so as to fill the entire contact surface between the sleeve 21 and the surface of the portion of at least one linear structural tube 51 and / or a portion of a support tube 52 and / or a portion of a connecting tube 53 disposed in the sleeve 21.When all the fixing holes 23, fixing channels 231 and the entire contact surface are filled, the fixing component 40 leaks through the outlet channel 24, indicating that the fixing component 40 has filled the entire expected contour within the joining element 20. In particular, the surface of the portion of the carbon tube that will be in the sleeve 21 and receive the fixing component 40 is prepared in a specific process in which it is sanded and the varnish on its surface is completely removed for the correct adhesion of the fixing component 40.
[0047] Thus, the fixing holes 23, the fixing channels 231 and the fixing component 40 form a kind of chemical rivet between the carbon of the main structure tubes 50 and / or other structural components and the joining elements 20.
[0048] In this sense, the fastening component 40 consists of a liquid adhesive composed of Ethyl cyanoacrylate in a range of 75 to 80% by mass and Bis(3,4-epoxycyclohexylmethyl) adipate in a range of 50 to 60% by mass. After curing this adhesive in the fastening holes 23, in the fastening channels 231 of the joining elements 20 and on the surface of a portion of at least one linear structural tube 51 and / or a portion of a support tube 52 and / or a portion of a connecting tube 53 disposed in the sleeve 21, the adhesive acts as a mechanical rivet in conjunction with the chemical fastening it provides, generating a double fastening redundancy that increases the structural strength of the final assembled component. Furthermore, the mechanical strength of the adhesive becomes greater than the strength of the material itself so that, in case of structural failure, this will occur in the tubes 51, 52, 53 before occurring in the joining elements 20.
[0049] According to figures 1 and 2, the remotely controlled aircraft 100, the object of this invention, comprises a wing 60, formed by two split modules, each split module comprising an assembly formed by an intrados 62 and an extrados 63 that are associated with each other and associated with a wing spar 61.
[0050] The lower surface 62 comprises internally a truss reinforcement 621 whose function is to distribute and support, in an improved manner, the bending and torsional forces that occur in the wing 60 during flight. Both the upper surface 63 and the lower surface 62 are made separately, both in injected expanded polypropylene (EPP), with the lower surface 62 being formed by injecting the expanded polypropylene (EPP) into the mold in which the truss reinforcement 621 is already positioned, that is, the lower surface 62 is formed together with the truss reinforcement 621.
[0051] In this sense, the choice of surface finish for the aerodynamic components of an aircraft, especially the wing, is a critical point. This is because the wing is the component responsible for generating lift in flight, and the presence of high roughness in this component directly damages the total lift force achieved by the aircraft and significantly increases the drag to be overcome, which consequently leads to a reduction in the autonomy of the desired mission, impairing stability and control, potentially leading to an overload on the autopilot and even a crash. For all these reasons, the aircraft 100, the subject of the present invention, uses expanded polypropylene (EPP) material in the construction of the wing, applied by injection and prepared to have an improved surface finish, without adding weight to the final structure. EPP also allows the aircraft 100 to continue its operation even in case of heavy rain.
[0052] As illustrated in Figure 2, wing spar 61 is formed by a pair of parallel spar tubes 611, 612 made of carbon fiber with diameters smaller than the diameter of the main structure tubes 50. These spar tubes 611, 612 are joined together by a core 613 also made of injected expanded polypropylene (EPP), so that the core 613 surrounds the inner surfaces of the spar tubes 611, 612 forming a single I-shaped cross-section profile with two carbon fiber tubes at each end and an EPP core.
[0053] For the assembly of wing 60, after each two-part module is correctly associated with each wing spar 61, this wing spar 61 is fixed to the outer surface of the reinforcing element 59 by means of an adhesive inserted, as described above, into the joining element 20 responsible for joining the wing spar 61 with the reinforcing element 59. More specifically, one wing spar 61 is fixed to the outer surface of the reinforcing element 59 that is fixed to the first pair of linear structural tubes 51 and another wing spar 61 is fixed to another outer surface of the reinforcing element 59 that is fixed to the second pair of linear structural tubes 51, so that the wing spars 61 are substantially linear with each other and with respect to the connecting tube 53.
[0054] The adhesive used for attaching wing spars 61 to reinforcement elements 59 was specifically developed to improve the bonding of EPP parts to carbon and nylon parts, resulting in a low final weight. Therefore, this adhesive is formed by an initial composition of: • diphenol epichlorohydrin-4,4'-isopropylidene between 50 and 70% by mass; • Silicon dioxide between 20 and 30% by mass; • a diluent between 5 and 10% by mass; and • Thermosetting resin between 0.25 and 1% by mass associated with a second composition of: • Silicon dioxide between 30 and 50% by mass; • an additive between 20 and 30% by mass; • benzyl alcohol between 5 and 10% by mass; • a healing agent comprising between 5 and 10% by mass; • amorphous silica and pyrophytic silica between 1 and 5% by mass; • Phenol between 2.5 and 3% by mass; • 2-(1-Piperazinyl) Ethylamine between 1 and 2.5% by mass; and • diphenol epichlorohydrin-4,4'-isopropylidene between 0.25 and 1% by mass.
[0055] The diluent for the first composition is 1,4-bis[(2,3-epoxypropoxy)methyl]cyclohexane, while the thermosetting resin used is 2,2'[methylenebis(p-phenylenexymethylene)]bisoxirane.
[0056] In the second composition, the additive is preferably a 2-propenonityl polymer with 1,3-butadiene and 1-cyano-1-methyl-4-oxy-4-[[2(1-piperaziayl)ethyl]amino]butyl-terminated, and the curing agents are isophorone diamine and N,N'-bis(3-aminopropyl)piperazine.
[0057] Aircraft 100 also comprises a two-part central body portion 54, as can be seen in figures 1 and 2, formed by an upper fairing 541 and a lower fairing 542 that fit together enclosing the connecting tube 53 and the auxiliary supports 55 of the main structure 50.
[0058] This central body portion 54 is positioned in the gap 58 of the main structure 50 between the reinforcement elements 59 and linearly in relation to the wing 60. Particularly, for greater wing stability 60, the central body portion 54 has the same width as the assembly formed by the lower surface 62 and the upper surface 63 of the wing 60.
[0059] The central body portion 54 comprises command and data processing modules such as, for example, electronic boards and circuits for receiving and processing remote commands received by the aircraft 100 and a redundant recovery system 80, among other possible instruments and components related to the operation of the remotely controlled aircraft 100.
[0060] Regarding the redundant recovery system 80, this comprises at least one parachute that is housed in the lower fairing 542 of the central body portion 54, as illustrated in figures 9 and 10. The function of the parachute is to operate in conditions where the rotors 30 or the forced landing controls directed to the rotors 30 and VTOL systems cannot be used, ensuring redundancy in safety in case of failures during operation.
[0061] To accommodate the parachute, a compartment was built into the lower fairing 542 of the central body portion 54 in which the parachute is placed folded and a lid 81 made of polycarbonate and with the exact dimensions of the compartment is positioned on top of it, which is released in case of parachute deployment. To prevent accidental openings, the cover 81 has a double fastening system consisting of a magnetic fastening using magnetic coins 82 arranged at two ends of the cover 81 and an electromechanical device 83. The electromechanical device 83 is equipped with sensors that prevent it from locking and, in case of aircraft failures 100, activate a rod 84 that makes contact with a laser sensor located in the electromechanical device 83 itself, indicating to the autopilot that it is time to shut down the cruise thruster 31. With the thruster 31 off, the propeller is braked, preventing it from snagging the parachute and blocking its opening.
[0062] The central body portion 54 also comprises a compartment that receives a payload device 90, as can be seen in Figure 8. The payload device 90 comprises a main component 92 that is interchangeable and attachable to a payload box 91. This main component 92 can be a camera, a gimbal, among others, which is positioned in a carbon fiber support 921 equipped with four quick-release screws. Thus, to attach the main component 92 to the payload box 91, the four quick-release screws are used in threaded holes located in the payload box 91.
[0063] Cargo box 91 is fitted into a compartment of the central body portion 54 specifically designed to receive the payload device 90. More specifically, cargo box 91 is preferably made of nylon, using 3D printing with the MJF technique. The cargo box 91 is secured simply by fitting it into its compartment in the lower fairing 542 of the central body portion 54, ensuring that the pressure latches 93, located on the sides of cargo box 91, are correctly locked into a female connector 94 located in the lower fairing 542 of the central body portion 54. The engagement of the pressure latches 93 in the female connector 94 connects the main component 92 to the aircraft's electronic controls 100.
[0064] When it is necessary to replace the main component 92 used by aircraft 100, the four quick-release screws are loosened, the main component 92 with the support 921 are removed, a new main component 92 is positioned on the support 921, and the main component 92 with the support 921 are again fixed to the payload box 91. In this way, the payload device 90 has a simplified operation, allowing the replacement of the main component 92 in the field, without the need to manually alter the center of gravity (CG), electrical wiring, or mechanical components, increasing the versatility of the operation.
[0065] Additionally, as can be seen in Figures 7 and 9, the remotely controlled aircraft 100, the object of this invention, also comprises an airflow measuring device 70, also known as a pitot tube. The function of the pitot tube in the aircraft is to measure the airflow and generate a return data of the aircraft's flight speed (airspeed) so that the control system is aware of the aircraft's current speed and thus avoids flying at high or low speeds, also allowing it to adjust the engine power as needed by the flight conditions. Thus, the airflow measuring device 70 was developed to be resistant to changes in wind and weather without compromising its measurements, thereby allowing the aircraft 100 to operate in heavy rain conditions without the need to load the aircraft 100 with extra devices and without generating increased noise or errors in speed readings.
[0066] For this purpose, this airflow measuring device 70 comprises a referentially cylindrical and substantially hollow body 77, provided with an inlet portion 75, an internal portion 71 and a data reading portion 76 linearly opposite to the inlet portion 75 and which is associated with the central body portion 54 of the main structure 50, as can be seen in figure 1.
[0067] Specifically, the inlet portion 75 comprises a dynamic pressure chamber 72 and at least one drain orifice 73 with a diameter of 3 mm is positioned adjacent to the dynamic pressure chamber 72, preferably just after the inlet of the dynamic pressure chamber 72. The drain orifice 73 communicates with at least one flow channel 74 to remove any water particles that enter the device 70 through the inlet portion 75. Additionally, a projection 78 is positioned just ahead of the inlet of the flow channel 74 to prevent the entry of water particles that could clog and impair the dynamic pressure reading sensor 79. With regard to static data acquisition, the multiple internal compartments 711 arranged along the internal portion 71 of the device 70 were designed to prevent water particles from reaching the sensor or obstructing the static pressure reading channels 76.Thus, with the barriers designed for device 70, speed reading errors are avoided, especially when aircraft 100 is operating in heavy rain conditions.
[0068] Therefore, the present invention proposes a remotely controlled vertical takeoff and landing (eVTOL) aircraft with electric propulsion, forming a fixed-wing quadcopter, which is not observed in the state of the art. This is because known quadcopter aircraft do not have as much autonomy as a fixed-wing aircraft, but they have more versatility for takeoff and landing. Thus, the combination of both operations expands the scope of operations and solves the problems of the state of the art in a single aircraft that provides flight autonomy for more demanding missions and operation in varied terrains with a small operating area.
[0069] For this purpose, the aircraft 100 object of the present invention comprises a main structure 50 robust enough to withstand the various stresses required while not having a high weight.
[0070] Additionally, the 100 aircraft has a construction that utilizes carbon structures with the integration of 20 nylon joining elements using the MJF (Multi Jet Fusion) technique and 60 wing structures and 541, 542 fairings made of expanded polypropylene (EPP), to generate high structural resistance combined with reduced weight, aiming for maximum autonomy for agricultural, aerial photogrammetry and military missions.
[0071] Having described a preferred embodiment, it should be understood that the scope of the present object encompasses other possible variations, being limited only by the content of the appended claims, including possible equivalents.
Claims
CLAIMS 1. Remotely controlled aircraft (100) with vertical takeoff and landing (VTOL), characterized in that it comprises (a) a main structure (50) to which at least one and preferably four rotors (30) are attached, the main structure (50) being formed by a plurality of tubes (51, 52, 53) connected to each other by means of joining elements (20) which receive a fastening component (40), the main structure (50) comprising (a.1) reinforcement elements (59) arranged parallel to each other, each reinforcement element (59) receives a wing spar (61) on which a wing (60) is mounted and fixed; and (a.2) a central body portion (54), disposed between the reinforcement elements (59), the central body portion (54) comprising command and data processing modules and a redundant recovery system (80); and (b) an airflow measuring device (70) comprising an inlet portion (75), an internal portion (71) in which at least one drain orifice (73) communicating with at least one flow channel (74) is disposed, and a data reading portion (76) linearly opposite to the inlet portion (75) and associated with the central body portion (54) of the main structure (50).
2. Remotely controlled aircraft (100), according to claim 1, characterized in that the main structure (50) is formed by a plurality of tubes (51, 52, 53) made of carbon, preferably the main structure (50) comprises an “H” shaped arrangement formed by a first pair of linear structural tubes (51) of the same diameter and connected to each other by a joining element (20) and a second pair of linear structural tubes (51) of the same diameter and connected to each other by a joining element (20), the first pair of linear structural tubes (51) being arranged parallel to the second pair of linear structural tubes (51) forming a gap (58), the first and second pairs of linear structural tubes (51) being connected to each other by a connecting tube (53) fixed concurrently to the first and second pairs of linear structural tubes (51) by joining elements (20).
3. Remotely controlled aircraft (100), according to claim 2, characterized in that the main structure (50) further comprises at least one and preferably four support tubes (52), at least one pair of support tubes (52) being associated with the first and second pairs of linear structural tubes (51) by means of joining elements (20) forming a four-support landing support.
4. Remotely controlled aircraft (100), according to claim 2, characterized in that at least one rotor (30) is associated with the ends of the first pair of linear structural tubes (51) and the second pair of linear structural tubes (51) forming a quadcopter configuration aircraft, said rotors (30) comprising electric propulsion powered by at least one Lithium-ion battery.
5. Remotely controlled aircraft (100), according to claims 1 to 3, characterized in that the joining element (20) is made of polyamide and by additive manufacturing, comprising a sleeve (21) that receives a portion of at least one linear structural tube (51) and / or a portion of a support tube (52) and / or a portion of a connecting tube (53), the sleeve (21) being provided with a plurality of fixing holes (23) and a plurality of fixing channels (231).
6. Remotely controlled aircraft (100), according to claim 5, characterized in that the joining element (20) further comprises an inlet channel (22) communicating with the plurality of fastening channels (231) and with the plurality of fastening holes (23) by means of a main channel (25) and an outlet channel (24), diametrically opposite to the inlet channel (22) and communicating with the plurality of fastening channels (231) and with the plurality of fastening holes (23).7.Remotely controlled aircraft (100), according to claim 6, characterized in that the joining element (20) receives the fastening component (40) through the entry channel (22), the fastening component (40) fills the plurality of fastening holes (23) and the plurality of fastening channels (231) and makes contact with the portion of at least one linear structural tube (51) and / or a portion of a support tube (52) and / or a portion of a connecting tube (53) disposed in the sleeve (21).
8. Remotely controlled aircraft (100), according to claim 7, characterized in that the fastening component (40) is a liquid adhesive composed of Ethyl cyanoacrylate in a range of 75 to 80% by mass and Bis(3,4 epxycyclohexylmethyl) adipate in a range of 50 to 60% by mass.
9. Remotely controlled aircraft (100), according to claim 1, characterized in that the wing (60) comprises two split modules, each split module comprising an assembly formed by an intrados (62) and an extrados (63), the intrados (62) comprising internally a truss reinforcement (621), the extrados (63) and intrados (62) assemblies being associated with each other and associated with the wing spar (61).
10. Remotely controlled aircraft (100), according to claim 9, characterized in that the extrados (63) and intrados (62) assemblies are made separately from injected expanded polypropylene (EPP), wherein the intrados (62) is formed from injected expanded polypropylene (EPP) together with the truss reinforcement (621).
11. Remotely controlled aircraft (100), according to claim 9, characterized in that the wing spar (61) is formed by a pair of parallel spar tubes (611, 612) made of carbon, the spar tubes (611, 612) being joined together by a core (613) formed of injected expanded polypropylene (EPP).
12. Remotely controlled aircraft (100), according to claim 11, characterized in that the wing spar (61) is fixed to an outer surface of the reinforcing element (59) by means of an adhesive formed by a first composition of epichlorohydrin-4,4'-isopropylidene diphenol between 50 and 70% by mass, silicon dioxide between 20 and 30% by mass, a diluent between 5 and 10% by mass and thermosetting resin between 0.25 and 1% by mass associated with a second composition of silicon dioxide between 30 and 50% by mass, an additive between 20 and 30% by mass, benzyl alcohol between 5 and 10% by mass, a curing agent between 5 and 10% by mass, amorphous silica and pyrogeneic silica between 1 and 5% by mass, phenol between 2.5 and 3% by mass, 2-(1-Piperazinyl) Ethylamine between 1 and 2.5% by mass and epichlorohydrin-4,4'-isopropylidene diphenol between 0.25 and 1% by mass.
13. Remotely controlled aircraft (100), according to claims 1 to 12, characterized in that the main structure (50) comprises a wing spar (61) fixed to each outer surface of the reinforcing element (59), the wing spars (61) being arranged substantially linearly with respect to each other and to the connecting tube (53).
14. Remotely controlled aircraft (100), according to claims 1 and 2, characterized in that the central body portion (54) is bipartite, formed by an upper fairing (541) and a lower fairing (542) that fit together enclosing the connecting tube (53), the central body portion (54) being disposed in the gap (58) of the main structure (50).
15. Remotely controlled aircraft (100), according to claims 1 and 14, characterized in that the redundant recovery system (80) comprises at least one parachute housed in the lower fairing (542) of the central body portion (54).
16. Remotely controlled aircraft (100), according to claims 1 and 14, characterized in that the central body portion (54) comprises a compartment that receives a payload device (90), the payload device (90) comprises an interchangeable main body (92) fixed to a payload box (91), the payload box is disposed fitted into the compartment of the central body portion (54).
17. Remotely controlled aircraft (100), according to claim 1, characterized in that at least one drain hole (73) is positioned adjacent to a dynamic pressure chamber (72) disposed in the inlet portion (75) of the airflow measuring device (70).