A system for slowing down the speed of flying objects by applying electrodynamic and aerodynamic braking forces. The system is comprised of plurality of stubs, where each stub is made of dielectric material surrounded by metal foil and another metal foil is inserted in the middle of the stub, where the outer metal foil and the inner metal foil are isolated from each other, so that they form a capacitor. Each stub is stored in a barrel before being used. When activated, the stubs are stretched from the barrel as a tail behind the flying object. The area of the stub generates aerodynamic drag. The stub capacitor is charged by a generator so that free electrons are present in the outer metal layer of the stub. The electric field produced by these charges interacts with ions in the atmosphere.

A system includes a surface, an actuator, and processing circuitry. The surface includes one or more non-actuating zones and one or more actuatable zones. The actuator is configured to a flow property of a fluid that flows over the one or more actuatable zones of the surface. The processing circuitry is configured to obtain a value of a parameter of the fluid that flows over the surface, and operate the actuator to adjust the flow property of the fluid that flows over the one or more actuatable zones based on the value of the parameter of the fluid.

An autonomous vehicle system includes a body and a plurality of sensors coupled to the body and configured to generate a plurality of sensor measurements corresponding to the plurality of sensors. The system also includes a control unit configured to: receive inputs from a plurality of sources wherein the plurality sources comprise the plurality of sensors, the inputs comprise the plurality of sensor measurements; determine a confidence level of each input based on other inputs; prioritize, based on the confidence level associated with each input, the inputs; generate, based on the prioritization of the inputs and the confidence level, a combined input with a combined confidence level; and determine, based on the combined input and the combined confidence level, a mission task to be performed.

An autonomous vehicle system includes a body and a plurality of sensors coupled to the body and configured to generate a plurality of sensor measurements corresponding to the plurality of sensors. The system also includes a control unit configured to: receive inputs from a plurality of sources wherein the plurality sources comprise the plurality of sensors, the inputs comprise the plurality of sensor measurements; determine a confidence level of each input based on other inputs; prioritize, based on the confidence level associated with each input, the inputs; generate, based on the prioritization of the inputs and the confidence level, a combined input with a combined confidence level; and determine, based on the combined input and the combined confidence level, a mission task to be performed.

Systems and methods are provided for experimentally determining optimized placement and operating conditions, e.g., amplitude, phase, or frequency, of active flow control actuators by executing an optimization routine to sequentially activate varying subsets of active flow control actuators of a plurality of active flow control actuators spatially distributed within a flow field, calculating a cost function of each of the subsets of sequentially activated active flow control actuators based on respective measurements of one or more parameters, e.g., integral variables or proxies to the integral variables, within the flow field by one or more sensors, and determining an optimal subset of active flow control actuators based on the respective cost functions of each of the subsets of sequentially activated active flow control actuators.

Systems and methods are described herein to implement transverse momentum injection at low frequencies to directly modify large-scale eddies in a turbulent boundary layer on a surface of an object. A set of transverse momentum injection actuators may be positioned on the surface of the object to affect large-scale eddies in the turbulent boundary layer. The system may include a controller to selectively actuate the transverse momentum injection actuators with an actuation pattern to affect the large-scale eddies to modify the drag of the fluid flow on the surface. In various embodiments, the transverse momentum injection actuators may be operated at frequencies less than 10,000 Hertz.

A cooling duct configured to introduce air flow to a cooling target device provided in a helicopter body of a helicopter includes a duct body, a front opening, an upper opening, a hinge, and a movable blade. The duct body is mountable below a main rotor of the helicopter to be adjacent to the cooling target device. The front opening is formed on a forward side of the helicopter body in the duct body. The upper opening is formed on an upper side of the helicopter body in the duct body. The hinge is disposed in an upper portion of the duct body and includes a pivot shaft extending in a lateral direction of the helicopter body. The movable blade with an end that is pivotally supported by the hinge is provided to be pivotable about the pivot shaft between a first position and a second position.

A cooling duct configured to introduce air flow to a cooling target device provided in a helicopter body of a helicopter includes a duct body, a front opening, an upper opening, a hinge, and a movable blade. The duct body is mountable below a main rotor of the helicopter to be adjacent to the cooling target device. The front opening is formed on a forward side of the helicopter body in the duct body. The upper opening is formed on an upper side of the helicopter body in the duct body. The hinge is disposed in an upper portion of the duct body and includes a pivot shaft extending in a lateral direction of the helicopter body. The movable blade with an end that is pivotally supported by the hinge is provided to be pivotable about the pivot shaft between a first position and a second position.

A flow body for a vehicle having a flow surface, as well as a skin system attached to the flow surface is proposed. The skin system has a top layer and a foam arrangement positioned between the flow surface and the top layer, wherein the top layer includes an elastic, surface-like material, wherein the foam arrangement includes a first layer of an elastic, compressible open cell foam, wherein the foam arrangement is bonded to the top layer. The skin system has a static shape in an unloaded state, in which the shape defines an outer surface geometry that directly follows the geometry of the respective flow surface, and the skin system has a deflected shape when the flow body is subjected to turbulent air flow. The deflected shape at least temporarily compresses the foam arrangement.

A flow body for a vehicle having a flow surface, as well as a skin system attached to the flow surface is proposed. The skin system has a top layer and a foam arrangement positioned between the flow surface and the top layer, wherein the top layer includes an elastic, surface-like material, wherein the foam arrangement includes a first layer of an elastic, compressible open cell foam, wherein the foam arrangement is bonded to the top layer. The skin system has a static shape in an unloaded state, in which the shape defines an outer surface geometry that directly follows the geometry of the respective flow surface, and the skin system has a deflected shape when the flow body is subjected to turbulent air flow. The deflected shape at least temporarily compresses the foam arrangement.