This application claims priority to German Patent Application No. 10 2018 116 164.6, filed Jul. 4, 2018, the content of such application being incorporated by reference herein in its entirety.
The present invention relates to an aircraft, in particular a fully electric vertical take-off and landing (VTOL) aircraft. The invention also relates to a corresponding power supply.
VTOL is the cross-language name given in the aerospace industry to any type of aircraft, drone or rocket that has the capability of lifting off and landing again substantially vertically and without a runway. This collective term is used below in a further sense that includes not just fixed-wing aircraft with wings, but rather also rotary-wing aircraft such as helicopters, gyrocopters, gyrodynes and hybrids such as composite or combination helicopters and convertiplanes. Short take-off and landing (STOL) aircraft, short take-off and vertical landing (STOVL) aircraft and vertical take-off and horizontal landing (VTHL) aircraft are also included.
The power requirement during the take-off and landing phase of a VTOL is high. The battery of an electrically driven VTOL according to the prior art therefore has to meet extremely high requirements not only in terms of its capacity but also in terms of its power density.
WO 2010/031384 A2, which is incorporated by reference herein, discloses a method for launching a drone by means of a launching catapult, which applies the launching energy, in such a way that the launching catapult is first aligned before the launch. Here, the launching catapult is covered by means of a screen, which is removed only after the alignment and immediately before the launch. DE10 2016 219 473 A1, which is incorporated by reference herein, relates to a drone for docking onto a vehicle. In this case, the drone comprises an energy storage element and a docking device for docking the drone onto the vehicle. Furthermore, the drone comprises at least one communication unit for communication with the vehicle and/or with an external device of a user of the vehicle as well as at least one position identification unit for detecting a position of the user of the vehicle. In this case, the drone is designed, after a predeterminable trigger able to be detected by the communication unit, to identify the position of the user by way of the position identification unit, to undock from the vehicle, to return to the user of the vehicle according to the detected position and to follow said user automatically.
DE10 2007 003 458 A1, which is incorporated by reference herein, describes a device for automatically supplying energy to a small battery-operated aerial vehicle in order to ensure a virtually uninterrupted use of the aerial vehicle and to avoid constantly providing an operator. For this purpose, a landing and loading platform is provided, which is assigned a battery magazine or underneath which a charging device is provided.
To solve the problem outlined above, an alternative energy source that does not contribute to the overall weight of the aircraft is proposed. This proposal is based on the following knowledge: the aircraft equipped with an on-board battery has a mass MeVTOL+MBatt and a rotor surface AeVTOL. For the power PeVTOL/Batt required for lift-off, the following holds true
When the battery is removed from the aircraft, for the power PeVTOL required for the lift-off thereof, the following holds true
A battery with its own rotors would have a mass MBatt+Moverhead and a rotor surface ABatt. In this case, for the power required for lift-off, the following holds true
When the following equation is satisfied, the power required overall for hovering is therefore reduced, with the result that an electrically driven VTOL having a coupled, autonomous flight battery would be advantageous:
In view of the foregoing, described herein is an aircraft, in particular a fully electric vertical take-off and landing aircraft in the above sense, and a power supply for such an aircraft according to the independent claims.
Further advantageous configurations of the invention are specified in the dependent patent claims. The aircraft may thus be equipped for instance with bent or even selectively bendable wings. A corresponding variant increases the effective wing surface in horizontal flight, without however increasing the footprint of the aircraft.
The aircraft may furthermore have a fast-charging battery system that provides the drive energy for vertical take-off and landing and horizontal flight and allows quick charging of the aircraft when stationary.
In this case, instead of free-moving rotors, a plurality of ducted fans, including of different sizes, may be used to drive the aircraft, as are known outside of the aerospace industry, for instance for hovercraft or fanboats. The cylindrical housing surrounding the fan may considerably reduce thrust losses caused by vortexes at the blade tips in such an embodiment. Suitable ducted fans may be aligned horizontally or vertically, designed so as to pivot between both positions or be covered by louvers during horizontal flight for aerodynamic reasons. Pure horizontal thrust generation using fixed ducted fans is additionally conceivable.
Finally, in addition to preferably fully autonomous operation of the aircraft, it is also possible to consider granting manual control to human pilots if they are sufficiently qualified, which gives the device according to aspects of the invention the greatest possible flexibility in terms of handling.
One exemplary embodiment of the invention is illustrated in the drawings and will be described in more detail below.
The terms ‘fan,’ ‘rotor’ and ‘propeller’ may be used interchangeably herein.
During the launch illustrated in
In this case, the aircraft 10 is the master and the drone 12 equipped with its own battery 15 is the slave. Both batteries 15 are connected to one another and supply power to both the aircraft 10 and the rotors 13 of the drone 12. A DC-to-DC converter 14 on board the drone 12 ensures that the voltages match and controls the flow of energy.
When the transition altitude is reached, the autonomous battery drone 12 is released and flies back to the ground. The aircraft 10 then continues the flight exclusively using its own on-board battery 15.
The aircraft 100 includes foldable wings 102. The wings 102 are shown in a folded configuration in
Rear propellers 104 are mounted on the trailing edge of the airfoils or wings 102 (i.e., the edge furthest from the nose 105). Propellers 104 may be referred to as cruising propellers because they are used during the cruising operation of the aircraft (at least in one position of the propellers 104). The propellers 104 are configured to pivot between two different positions, as shown in
Horizontally mounted propellers 106 are fixedly mounted and integrated into the wings 102. Unlike the propellers 104, the position of the propellers 106 is fixed, however, those skilled in the art will recognize that the propellers 106 could be modified so that they are pivotable between vertical and horizontal positions. The propellers 106 generate maximum vertical thrust for take-off and landing operations of the aircraft. The propellers 106 may also be referred to herein as lifting propellers.
The propellers 104 and 106, which may also be referred to herein as fans, may be operated by a fully-electric drive. To that end, a battery charging system 108 including a charger, an inverter and a fast-charging battery are positioned within the fuselage of the aircraft for powering the propellers 104 and 106. The fuselage may also be configured to carry one or more passengers.
A sealing ring 218 surrounds the louvers 216 and is moveable between a retracted position (
Number | Date | Country | Kind |
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102018116164.6 | Jul 2018 | DE | national |