Abstract:
A solar powered air vehicle that can stay aloft for indefinite periods of time. The vehicle employs photovoltaic solar cells for primary power and high speed counter-rotating flywheels for energy storage and steering of the vehicle. The flywheels are placed in the wing to reduce airfoil drag. A control law provides three-axis stabilized control of the vehicle by controlling propeller pitch to vary the speeds of the flywheels.
Abstract:
Methods and apparatuses for launching unmanned aircraft and other flight devices or projectiles are described. In one embodiment, the aircraft can be launched from an apparatus that includes a launch carriage that moves along a launch guide. The carriage can accelerate when portions of the carriage and/or the launch guide move relative to each other. A gripper carried by the launch carriage can have at least one grip portion in contact with the aircraft while the launch carriage accelerates along the launch axis. The at least one grip portion can move out of contact with the aircraft as the launch carriage decelerates, releasing the aircraft for takeoff. A brake can arrest the motion of the gripper after launch.
Abstract:
A span-loaded, highly flexible flying wing, having horizontal control surfaces mounted aft of the wing on extended beams to form local pitch-control devices. Each of five spanwise wing segments of the wing has one or more motors and photovoltaic arrays, and produces its own lift independent of the other wing segments, to minimize inter-segment loads. Wing dihedral is controlled by separately controlling the local pitch-control devices consisting of a control surface on a boom, such that inboard and outboard wing segment pitch changes relative to each other, and thus relative inboard and outboard lift is varied.
Abstract:
An aircraft arrangement for Mini or Micro UAV comprising a fore wing (14) and an aft wing (12) in tandem closed-coupled arrangement. The aft wing (12) has side panels (18) and control surfaces (19), and tapered planform with positive sweep, while the fore wing (14) has non-positive trailing edge sweep. The fore wing (14) and the aft wing (12) are disposed at different height, and the aircraft arrangement has no other wings or tail arrangements.
Abstract:
Methods and apparatuses for launching unmanned aircraft and other flight devices or projectiles are described. In one embodiment, the aircraft can be launched from an apparatus that includes a launch carriage that moves along a launch guide. The carriage can accelerate when portions of the carriage and/or the launch guide move relative to each other. A gripper carried by the launch carriage can have at least one grip portion in contact with the aircraft while the launch carriage accelerates along the launch axis. The at least one grip portion can move out of contact with the aircraft as the launch carriage decelerates, releasing the aircraft for takeoff. A brake can arrest the motion of the gripper after launch.
Abstract:
An aircraft with swept back wings and spoilers inlaid into the top surface near the tips of the wings. The aircraft also includes an elevator formed in the center back portion of the aircraft, which is also aft of the spoilers. It is aft to allow an auxiliary control in the elevator signal to cancel the unwanted pitch up moment caused by the spoilers only going up and being aft of the center of gravity of the aircraft. Roll is achieved with these spoilers by the direct action of the lift dumping on one side or the other and by taking advantage of the transformation of yaw into roll by the sweep back of the wings.
Abstract:
An in-flight refueling system for an unmanned aircraft is responsive to sensed forces acting on a refueling receptacle of the aircraft by a separate refueling probe, to control movements of the aircraft as it is being refueled to reduce the magnitude of the sensed forces and thereby maintain the coupling of the aircraft with the refueling probe.
Abstract:
This disclosure provides a solar rechargeable aircraft that is inexpensive to produce, is steerable, and can remain airborne almost indefinitely. The preferred aircraft is a span-loaded flying wing, having no fuselage or rudder. Traveling at relatively slow speeds, and having a two-hundred foot wingspan that mounts photovoltaic cells on most all of the wing's top surface, the aircraft uses only differential thrust of its eight propellers to turn. Each of five segments of the wing has one or more motors and photovoltaic arrays, and produces its own lift independent of the other segments, to avoid loading them. Five two-sided photovoltaic arrays, in all, are mounted on the wing, and receive photovoltaic energy both incident on top of the wing, and which is incident also from below, through a bottom, transparent surface. The aircraft includes hinges and actuators capable of providing an adjustable dihedral for the wing. The actuators can be motors or control surfaces. Alternately, the actuators can be movable masses within the wing, which may be capable of deforming the wing to alter the aerodynamics of the wing, and thereby actuate the hinges. Because of wing dihedral, the aircraft includes motors both above and below the center of drag, and the aircraft uses differential thrust to control aircraft pitch. The aircraft has a wide variety of applications, which include serving as a long term high altitude platform that serves to link a ground station using radio wave signals and a satellite using optical signals.
Abstract:
An unmanned flying vehicle comprises an autonomous flying wing having at least two wing portions arranged substantially symmetrically about a center portion. Each wing portion is pivotally attached to each adjoining portion such that the wing portions are foldable for storage and openable for deployment. A preferred form is the so-called seagull wing having four wing portions. The vehicles may be programmable from a mother aircraft whilst being borne to a deployment zone using a data link which may be wireless.
Abstract:
This invention relates to ring-wing aircraft and is suited particularly, although not exclusively, to use in micro-unmanned air vehicles (UAV's) with ring-wings. An aircraft (10) according to the invention comprises a ring-wing (11) defining a duct (16) with a longitudinally-extending central axis (31), propulsion means (15) located within the duct and moveable aerofoils (13, 18) for controlling the aircraft in flight, the ring-wing being truncated obliquely at one end, that end being the rear (11b) when in horizontal flight, to form a ring-wing with opposed sides of unequal length. This arrangement produces center of mass offset from the central axis of the ring-wing, the pendulum effect will ensure that the aircraft will roll so that its center of mass will always be at the lowest height possible when the aircraft is airborne. Therefore the aircraft has a preferred orientation, and the control surfaces can be oriented with respect to this preferred orientation. In addition, the oblique truncation at the rear keeps the center of mass towards the front of the aircraft thereby giving improved stability in all three axes.