UNMANNED AERIAL VEHICLE WITH ELECTROMAGNETIC SHIELDING BOX

Description

[0001] The present invention relates to an unmanned aerial vehicle, or remotely controlled unmanned aircraft.

[0002] Such a vehicle is still generally called an aerial drone, designated by the acronym UAV (from the English "Unmanned Aerial Vehicle"), or by the acronym UAS (from the English "Unmanned Air System"), or by the acronym RPAS (from the English "Remotely Piloted Aircraft System"), and includes: an autonomous electrical power source, a housing in the interior volume of which are arranged electronic equipment electrically powered by the power source, including an electronic autopilot, at least one controller of at least one motor and a radiofrequency transmitter / receiver for remote-controlled actuation of propulsion or lift of the aerial vehicle, at least one wing for maintaining flight by propulsion or lift on remote control of the electronic equipment.

[0003] This type of remotely controlled aerial vehicle is increasingly used in surveillance or maintenance and its casing advantageously includes an electrically conductive wall extending so as to protect the electronic equipment it contains from any external electromagnetic field. It thus makes it possible to protect its electronic equipment against electromagnetic interference which can disturb its stability in flight and the accuracy of its measurements or instructions. An example is for example illustrated and described in the utility model document CN 206384132 U. US 2012 / 0083945 A1 relates to a helicopter having a modular airframe, with several layers which can be easily connected, the layers which house the electronics (autopilot and navigation systems), the batteries, and the payload (including the camera system) of the helicopter. The document "RF shielding for multi-copter based electromagnetic metrology platforms", by Pienaar et al., discusses and tests the effectiveness of electrical shielding of an unmanned aerial vehicle.

[0004] A particularly sensitive application, because it concerns environments highly exposed to powerful electromagnetic fields, is the monitoring and maintenance of electricity transmission and / or distribution installations using high and very high voltage lines. While the structure proposed above may be sufficient in a fairly wide vicinity, the closest approach to electrical substations or high or very high voltage lines is likely to generate electric arcs and powerful electromagnetic fields against which this type of drone is in reality not sufficiently protected because it is insufficiently robust.

[0005] More generally, any application involving exposure to powerful electromagnetic fields is concerned, such as the monitoring and maintenance of a railway electrical network, or even any type of live electrical network or equipment.

[0006] It may therefore be desirable to design an aerial vehicle without a human on board which would at least partially overcome the aforementioned robustness problem.

[0007] An aerial vehicle without humans on board is therefore proposed, comprising: an autonomous electrical power source, a housing in the interior volume of which are arranged electronic equipment electrically powered by the power source, including an electronic autopilot, at least one controller of at least one motor and a radiofrequency transmitter / receiver for remote-controlled actuation of propulsion or lift of the aerial vehicle, the housing comprising an electrically conductive wall extending so as to protect this electronic equipment from any electromagnetic field external to the housing, at least one wing for maintaining flight by propulsion or lift on remote control of the electronic equipment, wherein each electronic equipment arranged in the housing is provided with a connection port to a reference electrical potential and this connection port is electrically connected to the conductive wall of the housing.

[0008] Thus, by connecting the connection ports to the reference potentials of the electronic equipment arranged inside the housing at the same potential value, this equipment is protected from any propagation of an electric arc between them inside the housing. By further ensuring that this potential value is that of the electromagnetically protective conductive wall of the housing, the propagation of electric arcs from the outside to the inside of the housing from one piece of equipment to another is prevented. It should be noted that this double improvement in the robustness of the aerial vehicle when it is confronted with intense electromagnetic fields is achieved without additional costs thanks to clever assembly.

[0009] Optionally, a telemetry device, a camera and a video transmitter are also arranged in the interior volume of the housing, electrically powered by the power source, each provided with a connection port to the reference electrical potential and electrically connected to the conductive wall of the housing via their connection port.

[0010] Optionally, at least one fan-type cooling device is also arranged in the interior volume of the housing, the latter being provided with heat dissipation holes.

[0011] Also optionally, at least one passive heat sink type cooling device is arranged in the interior volume of the housing in thermal contact with its conductive wall, the latter hermetically surrounding the interior volume of the housing.

[0012] Also optionally, an unmanned aerial vehicle according to the invention may comprise an electrically conductive chassis on an upper face of which the housing is arranged and electrically connected and on a lower face of which the autonomous electrical power source is arranged, itself arranged in the interior volume of at least one additional electrically conductive wall housing electrically connected to the chassis.

[0013] Also optionally, the autonomous electrical power source comprises at least one battery arranged inside said at least one additional housing further provided with opening / closing means for independent access for insertion and removal of said at least one battery.

[0014] Also optionally, an unmanned aerial vehicle according to the invention may further comprise at least one radiofrequency transmitting / receiving antenna fixed to a face of the housing opposite the chassis using at least one electrically conductive connector screwed into the conductive wall of the housing.

[0015] Also optionally, an unmanned aerial vehicle according to the invention may comprise at least three antennas, two of which are electrically connected to the video transmitter and one to the telemetry device, the latter integrating the radiofrequency transmitter / receiver function and being connected for data reception and transmission with the electronic autopilot.

[0016] Also optionally, the electronic autopilot includes an electronic compass that can be activated and deactivated by remote control.

[0017] Also optionally, an unmanned aerial vehicle according to the invention may comprise N controllers of N respective propeller motors laterally offset using at most N arms extending from the housing), with N≥2.

[0018] The invention will be better understood with the aid of the following description, given solely by way of example and with reference to the appended drawings in which: [ Fig.1 ] there figure 1 represents in assembled perspective view from above the general structure of an aerial drone according to an embodiment of the invention, [ Fig.2 ] there figure 2 represents in assembled perspective seen from below the aerial drone of the figure 1 , [ Fig.3 ] there figure 3 represents in assembled perspective view from above a chassis and four lateral arms of the aerial drone of the figure 1 , [ Fig.4 ] there figure 4 schematically represents the contents with electrical connections of an electronic equipment box of the aerial drone of the figure 1 , [ Fig.5 ] there figure 5 represents in assembled perspective view from above a motorized propeller of the aerial drone of the figure 1 , [ Fig.6 ] there figure 6 represents in assembled perspective view from above a structural element of mechanical protection of the propeller of the aerial drone of the figure 1 , [ Fig.7 ] there figure 7 illustrates a detail of electrical connection near the housing of the figure 4 , [ Fig.8 ] there figure 8 illustrates a detail of electrical connection in the vicinity of the motorized propeller of the figure 5 , And [ Fig.9 ] there figure 9 schematically represents in section an antenna connection of the aerial drone of the figure 1 .

[0019] Aerial drone 10 shown in perspective on the figure 1 comprises an autonomous electrical power source 12, consisting of at least one battery inserted in at least one housing, for example two batteries inserted in two housings 12A and 12B, a central housing 14, in the interior volume of which are arranged electronic equipment electrically powered by the power source 12, and four lateral wings 16A, 16B, 16C, 16D for maintaining the drone 10 in flight by propulsion or lift on remote control (not illustrated) of the electronic equipment of the central housing 14. In accordance with the present invention, the central housing 14 comprises an electrically conductive wall extending so as to protect the electronic equipment it contains from any external electromagnetic field. Similarly, the two housings 12A and 12B advantageously comprise electrically conductive walls extending so as to protect the batteries they contain from any external electromagnetic field.These also advantageously have rigid plastic shells for good electrical insulation of their cells. They do not optionally have a voltage sensor to limit the risks of electromagnetic disturbances, the latter being able to be placed at a junction of the two batteries inside the central housing 14.

[0020] The central housing 14 is more precisely mounted and fixed on a frame 18, under which the two housings 12A and 12B are also mounted and fixed. From the frame 18, there also extend laterally, from the central housing 14, four rigid arms 20A, 20B, 20C, 20D to the distal ends of which the four lateral wings 16A, 16B, 16C, 16D are fixed. They are also fixed to the frame 18 by their proximal ends. The frame 18 will be described more precisely with reference to the figure 3 . It is optionally but advantageously made of electrically conductive material, such as the conductive wall of the central housing 14 with which it is in contact by fixing so as to ensure an electrical connection to the same reference potential. Similarly, the four rigid arms 20A, 20B, 20C, 20D are advantageously made of electrically conductive material, such as the chassis 18 with which they are in contact by fixing so as to ensure an electrical connection to the common reference potential by electrical continuity between the conductive wall of the central housing 14, the chassis 18 and each rigid arm 20A, 20B, 20C, 20D.

[0021] The central housing 14 may be of any shape. In the non-limiting example of the figure 1 , it is a rectangular parallelepiped with a lower rectangular face of its conductive wall fixed to the chassis 18, a free upper rectangular face opposite the chassis 18 and four lateral rectangular faces. On one of the four lateral faces, called the front face, a through hole 22 is drilled for the facing arrangement of the lens of a video camera integrated in the interior volume of the central housing 14. On the upper face opposite the chassis 18 three radiofrequency transmission / reception antennas, for example at 5.8 GHz, are further fixed according to a mechanism which will be detailed with reference to the figure 9 . One of these three antennas, bearing the reference 24 and arranged in the vicinity of the front face of the central housing 14, is electrically connected to a telemetry device integrated in the interior volume of the central housing 14. The other two antennas, bearing the references 26, 28 and arranged in the vicinity of the rear face of the central housing 14, are electrically connected to a video transmitter integrated in the interior volume of the central housing 14. Finally, a set 30 of small holes drilled on the upper face of the central housing 14 near the two antennas 26 and 28 makes it possible to evacuate the heat dissipated by the electronic equipment integrated in the interior volume of the central housing 14. The electronic content of this interior volume will be detailed with reference to the figure 4 .

[0022] It will be noted that the holes 22, 30 provided in the conductive wall of the central housing 14 are sized so as not to break the electromagnetic protection that it must provide.

[0023] The 16A side wing has a 32A motorized propeller which will be detailed with reference to the figure 5 . This motorized propeller 32A is mounted and fixed on the distal end of the rigid arm 20A. The lateral wing 16A further comprises a structural element 34A for mechanical protection of the motorized propeller 32A, also mounted and fixed on the distal end of the rigid arm 20A, placed under the motorized propeller 32A. It will be detailed with reference to the figure 6 . The four side wings being identical, the side wing 16B also comprises a motorized propeller 32B and a mechanical protection structural element 34B, mounted in the same way on the rigid arm 20B, the side wing 16C comprises a motorized propeller 32C and a mechanical protection structural element 34C, mounted on the rigid arm 20C, and the side wing 16D comprises a motorized propeller 32D and a mechanical protection structural element 34D, mounted on the rigid arm 20D.

[0024] As shown in the figure 2 which illustrates the aerial drone 10 in perspective view from below, four feet 36A, 36B, 36C, 36D are mounted and fixed respectively under the distal ends of the four rigid arms 20A, 20B, 20C, 20D. They are for example each made up of two parallel plates connected by columns forming spacers (not illustrated), each of the two plates being in the shape of an inverted “A” with an upper lateral extension for mounting and fixing against the corresponding rigid arm. One of the two plates is for example made of electrically conductive material forming an enveloping part, which allows it, in view of its arrangement in the lower part of the drone 10 under the corresponding lateral wing, to deflect any possible electric arc so that it does not strike the other equipment of the drone 10. Its attachment to the corresponding rigid arm also allows an electrical connection to the common reference potential.The other of the two plates, forming a consolidation part, is for example made of fiberglass of the same thickness, to support the mass of the drone 10 when it is placed on the ground. The fiberglass can be replaced by any other composite material with higher mechanical strength than the enveloping part, in particular equivalent to or greater than that of the fiberglass.

[0025] More generally, each ground support foot is advantageously formed of at least one enveloping part made of electrically conductive material, whatever its structure and shape in plate, tubular or other, and a consolidation part made of material of higher mechanical resistance than the enveloping part, whatever also its structure and shape in plate, tubular or other. The aim is to obtain suitable mechanical resistance and the lowest possible overall density while maintaining an electrically conductive envelope.

[0026] It should be noted that a ground support foot may be provided per wing, or alternatively ground support feet on only part of the wings, or even no ground support foot under the wing(s), regardless of the number of wings.

[0027] The bottom view of the figure 2 further allows to note that independent accesses to the batteries can be arranged under the boxes 12A and 12B. They are thus protected against any external electromagnetic field like the electronic equipment integrated in the central box 14, while being able to be inserted or extracted completely independently. The two boxes 12A and 12B are also in contact with the chassis 18 by fixing so as to ensure an electrical connection to the common reference potential.

[0028] In terms of size, such an aerial drone 10 may have lateral dimensions of less than 1 m, a height of less than 25 cm and a weight of less than 3 kg. It is suitable, given the arrangement of its antennas above the central housing 14 and its mechanical protection structural elements 34A, 34B, 34C, 34D under the motorized propellers 32A, 32B, 32C, 32D for an approach from above of the intended target.

[0029] In terms of materials, the electrically conductive material used for the conductive walls of the housings 14 and 12A, 12B, the plates of the chassis 18, the rigid arms 20A, 20B, 20C and 20D and the conductive plates of the feet 36A, 36B, 36C and 36D is for example aluminum sheet 0.5 to 2 mm thick: for example 0.5 mm for the conductive walls of the housings, 1 mm for the conductive plates of the feet 36A, 36B, 36C and 36D, 1.5 mm for the rigid arms 20A, 20B, 20C and 20D and 2 mm for the plates of the chassis 18. Alternatively and for a gain in mass and rigidity, it is entirely possible to envisage a composite material including aluminum or any other conductive material and fiber of glass, carbon or plastic, by polymerization or metallization.

[0030] There figure 3 is a more detailed representation of a possible embodiment of the frame 18 and the four rigid arms 20A, 20B, 20C, 20D. The frame 18 consists of two parallel plates 18A (upper plate) and 18B (lower plate) of the same dimensions attached to each other by spacer. They are of rectangular main shape with diagonal fixing extensions at their four corners. Each rigid arm 20A, 20B, 20C or 20D is fixed and clamped between the two plates 18A and 18B along the corresponding diagonal extension, its proximal end extending towards the center of the two plates. It is thus the proximal ends of the four rigid arms 20A, 20B, 20C and 20D which fulfill the function of spacer to bring the two parallel plates 18A and 18B face to face. The electrical continuity of all these elements also makes the spacer itself electrically conductive. figure 3 further shows that the upper plate 18A has four holes 38A, 38B, 38C, 38D respectively arranged facing the four proximal ends of the four rigid arms 20A, 20B, 20C, 20D. Their function will be detailed with reference to figures 4 And 7 .

[0031] The upper plate 18A is intended to receive the central housing 14, while the lower plate 18B is intended to receive the two housings 12A and 12B.

[0032] There figure 4 represents in schematic section the central housing 14 of the figure 1 , its immediate environment and its content.

[0033] It comprises an electrically insulating inner wall 40, for example made of a plastic material such as polyoxymethylene with a thickness of 2 mm, and an electrically conductive outer wall 42 forming the aforementioned common reference potential, for example 0.5 mm thick. These two walls are placed against each other and pierced to form the hole 22 on the front face and the set 30 of small holes on the upper face. They are further pierced on the lower face with four holes for the passage of electrical wires. These four holes correspond to the four holes 38A, 38B, 38C, 38D of the upper plate 18A of the chassis 18 and are arranged opposite them when the central housing 14 is mounted and fixed on the chassis 18.

[0034] Alternatively and depending on the specific applications targeted, the internal wall 40 can be removed to lighten the aerial drone 10 if its electrical insulation function is not essential or desired.

[0035] Likewise, the housings 12A and 12B in which the batteries 44A and 44B are integrated have holes in their faces in contact with the lower plate 18B of the chassis 18, the latter also having corresponding holes.

[0036] Between the two plates 18A and 18B of the chassis, the four rigid arms 20A, 20B, 20C, 20D are hollow tubes, for example of rectangular or even square section 20x20 mm, closed at their two ends and each having two holes, one of which is against the upper plate 12A facing one of its holes 38A, 38B, 38C, 38D and the other is against the lower plate 12B facing one of its holes. Thus, passages are created between the interior volumes of the central housing 14, of the two housings 12A, 12B and of the four rigid arms 20A, 20B, 20C, 20D for the passage of electrical wires between certain electronic equipment integrated in the central housing 14 and the batteries 44A, 44B integrated in the housings 12A, 12B, or between certain electronic equipment integrated in the central housing 14 and the motorized propellers 32A, 32B, 32C, 32D offset laterally at the distal ends of the rigid arms 20A, 20B, 20C, 20D.More generally, the section of hollow tubes may not be rectangular, such as round or other.

[0037] The electronic equipment arranged in the interior volume of the central housing 14 comprises an electronic autopilot 46, four controllers 48A, 48B, 48C, 48D of motors of the motorized propellers 32A, 32B, 32C, 32D and a radiofrequency transmitter / receiver 50, connected for reception and transmission of data with the electronic autopilot 46, for remote-controlled actuation in propulsion or lift of the drone 10. They also optionally comprise a telemetry device, a camera 52, a video transmitter 54 and a fan-type cooling device 56.

[0038] As regards the electronic autopilot 46, its function is to send orders to the four controllers 48A, 48B, 48C, 48D based on orders received by remote control and inertial, barometric or other navigation sensors, to ensure the stability and movement of the drone 10. It optionally but advantageously includes an electronic compass that can be activated and deactivated by remote control. Such a compass is in fact sensitive to intense electromagnetic fields that may be added to the Earth's magnetic field. It can thus be activated while it is far from such an intense electromagnetic field, for automated heading maintenance, then be deactivated by remote control when it approaches a source of intense electromagnetic field, for example an electrical substation or a high-voltage electricity transmission and / or distribution line, a railway electrical network, etc., in which case the heading must then be maintained manually by the operator in possession of the remote control.

[0039] As for the controllers 48A, 48B, 48C and 48D, they supply power and control the rotation speeds of the motors of the motorized propellers 32A, 32B, 32C and 32D. There is one per motor. They are arranged inside the central housing 14 to limit the risks of disturbing the very sensitive wiring between each of them and the electronic autopilot 46.

[0040] With regard to the fan 56, its presence in the central housing 14 requires the set 30 of heat evacuation holes. But alternatively, for potential use of the drone 10 even in bad weather, it could be made waterproof by removing the set 30 of holes, ensuring that the conductive wall 42 hermetically surrounds the interior volume of the central housing 14 and replacing the fan 56 with a passive heat sink in contact with the conductive wall 42, for example by means of a thermal paste, for evacuation of the heat produced by the aforementioned electronic equipment via this conductive wall. The use of a passive heat sink in addition to the fan 56 is also conceivable. In this case, the walls 40 and 42 are provided with the set 30 of heat evacuation holes.

[0041] In the non-limiting example of the figure 4 , the radio frequency transmitter / receiver 50 is in fact integrated into the telemetry device, so that the latter is designated by the same reference. This is the reason why the telemetry device 50 is finally connected to the antenna 24, thus also enabling it to transmit telemetry data to the ground. Similarly, the video transmitter 54 is connected to the antennas 26 and 28.

[0042] As regards the power supplies, the telemetry device 50 and the camera 52 are electrically powered by the battery 44A using electrical wires passing through the holes provided for this purpose in the walls of the central housing 14, in the plates of the chassis 18, in the corresponding rigid arm(s) and in the wall of the housing 12A. The electronic autopilot 46 and the video transmitter 54 are electrically powered by the battery 44B using electrical wires passing through the holes provided for this purpose in the walls of the central housing 14, in the plates of the chassis 18, in the corresponding rigid arm(s) and in the wall of the housing 12B. As for the controllers 48A, 48B, 48C, 48D and the fan 56, they can be powered indirectly by the battery 44B, as illustrated in the figure 4 , via the electronic autopilot 46. They could just as well, as a variant, be powered directly by one or other of the two batteries 44A, 44B.

[0043] More generally, with regard to the equipment of the aerial drone 10, any other equipment than that indicated previously could be added, in the central housing 14 or elsewhere, in particular any other electronic, electrical, mechanical, electromechanical equipment, etc., while remaining compatible with the general principles of the present invention.

[0044] According to a first aspect, relating to the present invention, the electronic autopilot 46, the controllers 48A, 48B, 48C, 48D and the radiofrequency transmitter / receiver integrated in the telemetry device 50 are each provided with a connection port to a reference electrical potential and all these connection ports are electrically connected to the electrically conductive external wall 42 forming the aforementioned common reference potential. Where appropriate, that is to say when they are themselves present in the central housing 14, the camera 52, the video transmitter 54 and the fan 56 are also provided with connection ports to the reference electrical potential, all electrically connected to the external wall 42. In this way, all these electronic devices integrated in the central housing 14 are electromagnetically protected, between themselves and with respect to the outside, against any electric arc or intense electromagnetic field.

[0045] Any of the side wings 16A, 16B, 16C, 16D, rotating and propeller-driven, will now be detailed with reference to the figures 5 et 6 . More specifically, any one of the side-wing motor propellers 32A, 32B, 32C, 32D is illustrated in the figure 5 and is generally identified by the reference 32. More specifically also, any of the side wing protection structural elements 34A, 34B, 34C, 34D is illustrated in the figure 6 and is generally identified by reference 34.

[0046] The 32 motorized propeller of the figure 5 comprises a base 58 on which is fixed a cylindrical motor 60 with integrated electromagnetic protection. On the rotational drive axis of this cylindrical motor 60 is screwed a propeller 62 with two blades made of dielectric material, using a nut 64 made of dielectric material or covered with a cap made of dielectric material to prevent any electric arc reaching the motor 60 from above. This dielectric material can be plastic or, for better mechanical strength, a composite made of fiberglass, carbon or equivalent. The base 58 is extended longitudinally by two tabs, one upper 58A, the other lower 58B, for fixing to the distal end of one of the rigid arms 20A, 20B, 20C and 20D. This distal end of the rigid arm is intended to fit between the two tabs up to the inside of the base 58 in which a recess of corresponding shape is provided.The motorized propeller 32 is fixed by screwing the tabs onto the rigid arm in question.

[0047] It will be noted that the cylindrical motor 60 is advantageously, and in a manner known per se, electrically connected to the aforementioned common reference potential, for example via the base 58 and the corresponding distal end of the arm.

[0048] A hole 66 is provided in the upper part of the base 58 as close as possible to the cylindrical motor 60. This hole corresponds to a hole in the distal end of the rigid arm intended to be fitted into the base 58, arranged opposite when the rigid arm is correctly fitted, for the passage of electrical power supply wires in line with the cylindrical motor 60.

[0049] The mechanical protection structural element 34 of the figure 6 comprises, according to a second aspect, an electrically conductive strip 68.

[0050] This conductive strip 68 may be an added element, for example made of aluminum sheet, which extends over the periphery of the mechanical protection structural element 34, in particular in contact with the latter, and which is designed to be electrically connected to the conductive wall 42 of the central housing 14. This connection may be made directly or indirectly depending on the configuration of the aerial drone 10. Thus, the motorized propeller 32 which is mechanically protected by the structural element 34 is also electromagnetically protected against any electric arc or intense electromagnetic field. In the non-limiting example of figures 1, 2 And 6, the two ends of the conductive strip 68 are configured to be fixed along the distal end of the rigid arm which carries the structural element 34. Since this rigid arm is itself made of electrically conductive material and electrically connected to the conductive wall 42 of the central housing 14, the electrical connection to the common reference potential is indirect in this case.

[0051] The conductive strip 68 may alternatively be formed by surface treatment, for example by metallization, that is to say by direct deposition of an electrically conductive material on the periphery of the mechanical protection structural element 34, according to an appropriate surface treatment method.

[0052] More specifically, the mechanical protection structural element 34 of the figure 6 is in the form of a portion of a wheel, arranged under and centered on the motorized propeller 32 which it protects. Its radius is also greater than the length of each blade of the propeller 62. It comprises, for example, a central support 70, in the shape of a “U” or other, intended to surround laterally and to be fixed on the base 58 of the motorized propeller 32, a rim 72 in a circular portion and several spokes, for example four spokes 74, 76, 78, 80 slightly curved upwards at their distant ends, including two external spokes 74 and 80 between the distant ends of which the rim 72 extends circularly. All these elements 70, 72, 74, 76, 78 and 80 which constitute it are, for example, made of a dielectric material such as rigid plastic or other.

[0053] Alternatively, the mechanical protection structural element 34 could take a shape other than the wheel portion, for example a polygonal shape whose vertices would advantageously constitute preferred deflection points for potential electric arcs.

[0054] To return to the non-limiting example of the figure 6 , the motorized propeller 32 is thus centered in the support 70 and in the circle partially formed by the rim 72. The conductive strip 68 then extends circularly on the outer periphery of the rim 72, in particular in contact with an outer face of the latter, as an added part or formed by metallization, linearly along the outer edges of the two outer spokes 74 and 80 to the central support 70, then along the distal end of the rigid arm embedded in the base 58 of the motorized propeller 32. It is fixed along this distal end so as to make the electrical connection to the common reference potential with the rigid arm. This fixing can also be done in electrical contact with the conductive lateral extension of the foot 36A, 36B, 36C or 36D which is located under this distal end.Thus, the mechanical protection structural element 34 is fixed to the distal end of the rigid arm which carries it by its central support 70, using the ends of the conductive strip 68 and the base 58 which it surrounds.

[0055] There figure 7 illustrates in cutaway perspective a detail of the aerial drone 10 in the vicinity of any one of the holes 38A, 38B, 38C, 38D. This hole is identified by the general reference 38. This vicinity is also that of the proximal end of any one of the rigid arms 20A, 20B, 20C, 20D, identified by the general reference 20, of any one of the controllers 48A, 48B, 48C, 48D, identified by the general reference 48, of any one of the two batteries 44A, 44B, identified by the general reference 44, and of any one of the two boxes 12A, 12B, identified by the general reference 12.

[0056] It is clearly visible the passages which are created between the interior volumes of the central housing 14, the housing 12 and the rigid arm 20 for the passage of electrical wires. These interior volumes communicate with each other to create a space protected from electric arcs and external electromagnetic fields taking into account the contacting and electrically conductive walls of the central housing 14, the housing 12 and the rigid arm 20.

[0057] A first set of electrical wires 82, consisting of at least one pair of electrical wires electrically insulated from each other using dielectric sheaths and twisted into strands, electrically connects at least one of the electronic equipment of the central housing 14, for example the autopilot 46, the telemetry device 50, the camera 52 or the video transmitter 54 to the battery 44.

[0058] But above all, in accordance with a third aspect, a second set of electrical wires 84, consisting of three electrical wires each sheathed in an electrically insulating layer, that is to say a dielectric layer, and all three twisted into a strand, connects the controller 48 to the cylindrical motor 60 that it controls but which is laterally offset. In this way, each cylindrical wing motor 60 is electrically powered by electrical wires 84 which extend inside the corresponding rigid lateral offset arm 20 while being electrically insulated from its conductive wall. Thus, the electrical power supply of the motor 60 of each laterally offset wing is also fully protected electromagnetically and against electric arcs likely to be generated by any approach to an electrical substation, a high or very high voltage line, or any other equipment that is a source of an intense electromagnetic field.

[0059] The figure 8 illustrates in perspective a detail of the aerial drone 10 in the vicinity of the distal end of any one of the rigid arms 20A, 20B, 20C, 20D, identified by the general reference 20. It illustrates the exit of the second set of electrical wires 84 in line with the motor 60 through the hole 66. It can clearly be seen that this hole 66, pierced in the upper part of the base 58 in the continuity of the upper tab 58A, is located in the interior space delimited by the conductive strip 68 which electromagnetically protects the mechanical protection structural element 34 carried by the rigid arm 20.Thus the exit of the second set of electric wires 84 to the right of the motor 60, constituting an area of ​​electromagnetic fragility of the drone 10 although it is as close as possible to the motor 60, in particular a potential electric arc initiation area, is nevertheless also protected by this conductive strip 68 which diverts towards it any electric arc which would otherwise be likely to damage the exit of wires through the hole 66.

[0060] There figure 8 further illustrates the electrical connection which is made by mechanical contact of the conductive materials between the leg 36, generally identifying any of the legs 36A, 36B, 36C and 36D, the conductive strip 68 and the distal end of the arm 20.

[0061] There figure 9 illustrates in section and in detail the connection of any one of the three antennas 24, 26, 28 with the corresponding electronic equipment 50 or 54 and its fixing on the central housing 14.

[0062] The base of the antenna 24, 26 or 28 is for example provided with a first coaxial connector 86 with a central pin of the SMA type (from the English “SubMiniature version A”), while a second coaxial connector 88 with a central receptacle of the SMA type is secured to the electronic equipment 50 or 54. This second coaxial connector 88 is screwed into a hole drilled in the walls 40 and 42 of the central housing 14. A nut 90 and an internally toothed lock washer 92 ensure its retention without damaging the housing 14, in particular its conductive outer wall 42. The first coaxial connector 86 is screwed around the threaded upper end of the second coaxial connector 88 to make a central connection 94 of the antenna 24, 26 or 28 with the electronic equipment 50 or 54. This central connection 94 is surrounded by an electrically insulating cylindrical layer 96, i.e. a dielectric layer, inside the second coaxial connector 88.

[0063] The second coaxial connector 88 (except for its inner cylindrical layer 96), the lock washer 92 and the nut 90 are made of electrically conductive material, for example brass. The portion of electronic equipment 50 or 54 visible on the figure 9 is then advantageously made of electrically conductive material so as to make the electrical connection to the reference potential mentioned above at the base of the antenna 24, 26 or 28. The latter is advantageously sheathed in an electrically insulating material, i.e. a dielectric material, so that, in the figure 9 , the sheath of the antenna 24, 26 or 28, the inner cylindrical layer 96 of the second coaxial connector 88 and the wall 40 of the housing 14 are electrically insulating.

[0064] It is clear that an unmanned aerial vehicle such as the one described above makes it possible to approach areas with an intense electromagnetic field with optimal safety, such as electrical substations or high or very high voltage electricity transmission and / or distribution lines or any other electrical equipment that is a source of an intense electromagnetic field.

[0065] It should be noted, however, that the first, second and third aspects presented above are independent inventive concepts, although they are advantageously complementary.

[0066] Thus, an aerial drone according to the first aspect of the present invention may have one or more wing(s) of any kind, in particular not necessarily motorized, with propeller(s) or lateral(s), with or without structural element(s) for mechanical protection. It may be a fixed wing, a mobile wing (for example with propeller), or even a hybrid wing, that is to say, combining a fixed part (such as a wing for example) and a mobile part (such as a propeller for example). The housing 14 integrating the electronic equipment is also not necessarily central. In particular, in the absence of a structural element for mechanical protection of the wing, the question of a combination with the second aspect does not arise. In particular also, in the absence of a motorized wing offset laterally by a rigid arm, the question of a combination with the third aspect does not arise either.

[0067] Similarly, an aerial drone according to the second aspect may have one or more rotary wings with motorized propeller(s) without it necessarily being laterally offset. The housing 14 integrating the electronic equipment is also not necessarily central. In particular, in the absence of a motorized wing laterally offset by a rigid arm, the question of a combination with the third aspect does not arise. It would also be possible to envisage a drone according to the second aspect in which the electronic equipment of the housing 14 would not be connected to a common reference electrical potential formed by its conductive wall, which would then not be in accordance with the first aspect of the present invention.

[0068] Similarly, an aerial drone according to the third aspect may have one or more laterally offset motorized wings using one or more rigid arms without it necessarily having propeller(s) and mechanical protection structural element(s). It may be a fixed, mobile (for example propeller) or even hybrid motorized wing. In particular, in the absence of a mechanical protection structural element for the wing, the question of a combination with the second aspect does not arise. It would also be possible to envisage a drone according to the third aspect in which the electronic equipment of the housing 14 would not be connected to a common reference electrical potential formed by its conductive wall, which would then not be in accordance with the first aspect of the present invention.

[0069] It will also be noted, and as has just been demonstrated above, that the invention is not limited to the embodiment described above.

[0070] For example, a drone with four controllers of four respective propeller motors laterally offset using four arms extending from the housing 14 has been illustrated and described. However, for a drone with lateral offset of motorized wings, it is more generally possible to envisage N offset wings, with N≥2 and not necessarily equal to four. In this case, different embodiments involving N controllers of N respective propeller motors laterally offset using at most N arms extending from the housing 14 are conceivable.

[0071] It will more generally appear to those skilled in the art that various modifications may be made to it in light of the teaching just disclosed to them. In the detailed presentation of the invention given above, the terms used should not be interpreted as limiting the invention to the embodiment set forth in the present description, but should be interpreted to include all equivalents the prediction of which is within the reach of those skilled in the art by applying their general knowledge to the implementation of the teaching just disclosed to them.

Claims

1. An unmanned aerial vehicle (10) comprising: - a self-contained electrical power source (12; 44A, 44B), - a housing (14) in the interior volume of which electronic equipment (46, 48A, 48B, 48C, 48D, 50, 52, 54, 56) electrically powered by the power source (12; 44A, 44B) is arranged, including an electronic autopilot (46), at least one controller (48 ; 48A, 48B, 48C, 48D) of at least one motor (60) and a radio-frequency transmitter / receiver (50) for remote-controlled propulsion or lift actuation of the aerial vehicle (10), the housing (14) comprising an electrically conductive wall (42) extending so as to protect this electronic equipment (46, 48A, 48B, 48C, 48D, 50, 52, 54, 56) from any electromagnetic field outside the housing (14), - at least one wing (16A, 16B, 16C, 16D) for maintaining flight by propulsion or lift on remote control of electronic equipment, characterized in that each piece of electronic equipment (46, 48A, 48B, 48C, 48D, 50, 52, 54, 56) arranged in the housing (14) is provided with a connecting port for connecting to a reference electrical potential and in that this connecting port is electrically connected to the conductive wall (42) of the housing (14), this conductive wall fulfilling said function of reference electrical potential, so as to electrically protect, between each other and with respect to the outside, all the electronic equipment (46, 48A, 48B, 48C, 48D, 50, 52, 54, 56) integrated in the housing (14), against any electric arc or intense electromagnetic field.

2. The unmanned aerial vehicle (10) according to claim 1, wherein a telemetry device (50), a camera (52) and a video transmitter (54) are also arranged in the interior volume of the housing (14), electrically supplied by the power source (12; 44A, 44B), each provided with a connecting port for connecting to the reference electrical potential and electrically connected to the conductive wall (42) of the housing (14) via their connecting port.

3. The unmanned aerial vehicle (10) according to claim 1 or 2, wherein at least one fan-type cooling device (56) is arranged in the interior volume of the housing (14), the latter being provided with heat-removal holes (30).

4. The unmanned aerial vehicle (10) according to claim 1 or 2, wherein at least one cooling device of passive heat sink type is arranged in the interior volume of the housing (14) in thermal contact with its conductive wall (42), the latter hermetically surrounding the interior volume of the housing (14).

5. The unmanned aerial vehicle (10) according to any of claims 1 to 4, comprising an electrically conductive frame (18), on an upper side (18A) of which the housing (14) is arranged and electrically connected, and on a lower side (18B) of which the self-contained electrical power source (12; 44A, 44B) is arranged, itself arranged in the interior volume of at least one additional housing (12A, 12B) with an electrically conductive wall electrically connected to the frame (18).

6. The unmanned aerial vehicle (10) according to claim 5, wherein the self-contained electrical power source (12; 44A, 44B) comprises at least one battery (44A, 44B) disposed within said at least one additional housing (12A, 12B) further provided with opening / closing means for independent access for insertion and removal of said at least one battery (44A, 44B).

7. The unmanned aerial vehicle (10) according to claim 5 or 6, further comprising at least one radio-frequency transmitter / receiver antenna (24, 26, 28) fixed to a face of the housing (14) opposite the frame (18) by means of at least one electrically conductive connector (88) screwed into the conductive wall (42) of the housing (14).

8. The unmanned aerial vehicle (10) according to claims 2 and 7, comprising at least three antennas (24, 26, 28), two of which are electrically connected to the video transmitter (54) and one to the telemetry device (50), the latter integrating the radio-frequency transmitter / receiver function and being connected for data reception and transmission with the electronic autopilot (46).

9. The unmanned aerial vehicle (10) according to any of claims 1 to 8, wherein the electronic autopilot (46) comprises an electronic compass which can be activated and deactivated by remote control.

10. The unmanned aerial vehicle (10) according to any of claims 1 to 9, comprising N controllers (48; 48A, 48B, 48C, 48D) of N respective motors (60) of propellers (62) laterally offset by means of at most N arms (20; 20A, 20B, 20C, 20D) extending from the housing (14), with N≥2.