An unmanned aerial vehicle includes a propulsion system having at least one propulsion module comprised of at least one propeller and at least two motors/engines, one or more of the motors/engines providing mechanical energy to drive the propeller, wherein the difference between the angular velocities of the motors/engines provides energy input to a mechanical or magneto-mechanical linkage system to change the blade pitch angle of the propeller, in cyclic and/or collective manner.

A coaxial twin-propeller twin-motor aerial vehicle comprises an upper propeller (1), a lower propeller (2) and an aerial vehicle body (3). A first motor (4) and a second motor (5) are disposed in the aerial vehicle body (3). The first motor (4) is connected to the lower propeller (2) through a first transmission shaft (42). The second motor (5) is disposed below the first motor (4) and is connected to the upper propeller (1) through a second transmission shaft (52). The second transmission shaft (52) passes through the first motor (4), the first transmission shaft (42), and the lower propeller (2) sequentially and then is connected to the upper propeller (1). The second transmission shaft (52) and the first transmission shaft (42) are coaxial. The upper propeller (1) and the lower propeller (2) rotate at the same speed and in opposite directions under the drive of their individual motors.

An aircraft having a fixed wing is operative to perform vertical takeoff and landing while positioned in a nose-down orientation. The aircraft has a fixed wing having a leading edge and a trailing edge; a propulsion system operative to selectively provide forward propulsion and rearward propulsion; and a controller operative to control operation of the propulsion system. The propulsion system provides rearward propulsion during takeoff of the aircraft to move the aircraft in a direction of the trailing edge of the fixed wing, and provides forward propulsion during flight of the aircraft to move the aircraft in a direction of the leading edge of the fixed wing. The aircraft maintains the wing substantially vertical with the trailing edge facing upwards during takeoff, and transitions to having the wing substantially horizontal during flight. A vertical landing procedure is also provided.

An unmanned flying device including a body; a first blade and at least a second blade; a coupling assembly for coupling the first blade and the at least second blade to the body, wherein the coupling assembly urges the collapsing of the first blade and the at least second blade towards the body; and wherein both the first blade and the at least second blade are rotateable about the body, and wherein the first blade and the at least second blade are deployable away from the body via rotation of the first and the at least second blades about the body.

A storage and release mechanism for aerial distribution and release of insects from an unmanned aerial vehicle, the release being aimed at controlling a wild insect population, the wild population having fluctuating local densities, the mechanism comprising a switch for switching between two or more different sustainable insect delivery rates for release of the insects. The method is particularly suitable for sterile male mosquitoes in programs to control wild mosquito populations.

Multiple propeller blades may be joined by tip connectors to form a closed propeller apparatus. The tip connectors may create continuous structure between adjacent tips of a first propeller and a second propeller. Use of the tip connectors may reduce vortices created near the tips of the propeller blades, which cause drag and slow the rotation of the propeller blades. The tip connectors may also reduce noise caused by rotation of propeller blades. Further, the tip connectors reduce or eliminate deflection of the propeller blades by creating a support structure to counteract forces that would otherwise cause deflection of the propeller blades, thereby improving propeller blade loading. In some embodiments, the tip connectors may be formed of a malleable material and/or include one or more joints that enable at least one of the propellers to modify a pitch of blades of the propeller.

A multi-rotor aerial vehicle comprises at least two rotors, a controller, a power supply having an output shaft, a shaft-driven hydraulic machine coupled to the output shaft and at least two rotor-driving hydraulic machines coupled to respective rotors. At least one of the hydraulic machines is an electronically commutated hydraulic machine in which displacement of hydraulic fluid through each working chamber is regulated by electronically controllable valves, during each cycle of working chamber volume, in phased relationship to cycles of working chamber volume. The controller controls the electronically controllable valves of the electronically commutated hydraulic machines to independently control the rotation of the rotors. The shaft-driven hydraulic machine may be an electronically commutated machine with a plurality of independent outputs, which independently drive the rotor-driving hydraulic machines. The rotor-driving hydraulic machines may be electronically commutated machines the displacement of which is independently controlled to independently drive the rotors.

A foldable wing system for an unmanned aerial system having a fuselage includes a left wing frame having an inboard gear rotatably coupled to the fuselage, a right wing frame having an inboard gear rotatably coupled to the fuselage and a wing actuator coupled to a linkage point on at least one of the wing frames. The wing frames are movable between a plurality of positions including a deployed position and a stowed position. The inboard gear of the left wing frame is engaged with the inboard gear of the right wing frame such that the wing frames move symmetrically between the plurality of positions in response to movement of the linkage point by the wing actuator.

In some embodiments, an aircraft includes a flying frame having an airframe, a distributed propulsion system attached to the airframe, a flight control system operably associated with the distributed propulsion system and a pod assembly selectively attachable to the flying frame. The distributed propulsion system includes a plurality of propulsion assemblies that are independently controlled by the flight control system, thereby enabling the flying frame to have a vertical takeoff and landing mode and a forward flight mode.

A single-shaft aerial vehicle comprises a propeller, an aerial vehicle body and a wing driver unit constituting a portion of the aerial vehicle body. The aerial vehicle body has a streamlined shape. A ring-shaped wing extending out of the wing driver unit is provided at a central position of the wing driver unit. The ring-shaped wing is movable horizontally under the drive of the wing drive unit. When drag areas of the ring-shaped wing extending out of an outer circumference of the wing drive unit are the same in all directions, the single-shaft aerial vehicle maintains its current flying posture. When the ring-shaped wing moves toward a certain direction to increase the drag area extending out of the wing drive unit in the certain direction, and contracts into the wing drive unit in its opposite direction to reduce the drag area in the opposite direction, the single-shaft aerial vehicle changes its current flying posture.