Abstract: A structural element includes a first component and a second component; a bonded joint, by which the first component and the second component are interconnected; and an indication bolt, which is fixed to the first component and the second component. The indication bolt is designed to indicate when the first component and the second component have moved relative one another.

Abstract: A cooperative actuator system for active flow control, a vehicle comprising such cooperative actuator system, and a method for operating an actuator system for active flow control. The cooperative actuator system includes actuators, a control unit, and a data unit. The actuators are distributed along the surface in at least a first group and a second group downstream of the first group. The control unit is configured to control the actuators of the first group so that they form a first flow structure along the surface. The data unit is configured to provide data of the first flow structure. The control unit is further configured to control the actuators of the second group based on the data of the first flow structure, so that the actuators of the second group cooperatively interact with the first flow structure to form a second flow structure along the surface.

Abstract: The invention relates to a solar cell assembly comprising at least one first solar cell and at least one discrete protective diode (101) that is connected to the solar cell. The aim of the invention is to comprehensively protect a solar cell, a solar cell composite or a string of cells by means of one or more protective diodes, without resorting to the use of the material of the solar cells. To achieve this, in addition to a front and a rear contact (13, 15), the protective diode comprises an additional contact (14) that is placed at a distance from the front contact and is electrically connected to said contact via a p/n junction. A connector leads from the additional contact to a second solar cell, the latter in turn being connected to the first solar cell in a string.

Abstract: A self-diagnostic accelerometer (SDA) field programmable gate array (FPGA) may be capable of real time or near-real time diagnostic processing to determine potential accelerometer issues during flight or other mission critical operational situations. The SDA FPGA may determine accelerometer structural health and an attachment condition using an electronics system that is smaller, more energy efficient, and more cost effective than previous diagnostic tools. Advantages of the system may include diagnosing sensors automatically, immediately, actively (i.e., confirming the fault), and consistently, without the influence of a human operator. Customizable SDA algorithms may be adjusted to the specific needs of the sensor/environment.

Abstract: Disclosed is a satellite payload device, including a plurality of sensors configured to detect images of a satellite, a video distribution and storage unit configured to collect, compress, store, and transmit the images, and a control computer configured to request a portion of the plurality of sensors from which to receive sensor data that is routed to the video distribution and storage unit.

Abstract: A method and device enable the linear separation of two elements attached to each other, through two respective connecting surfaces of these two elements. A connecting layer is placed between both connecting parts. Thermite is used to melt this connecting layer. The thermite can be placed on the other side of the first connecting part towards the first element, a heat protecting plate completing this assembly. The thermite can also be placed in grooves provided on the connecting surface of the second connecting plate to be directly in contact with the connecting layer.

Abstract: A method of forming low-energy x-ray absorbers. Sensors may be formed on a semiconductor, e.g., silicon, wafer. A seed metal layer, e.g., gold, is deposited on the wafer and patterned into stem pads for electroplating. Stems, e.g., gold, are electroplated from the stem seed pads through a stem mask. An absorber layer, e.g., gold, is deposited on the wafer, preferably e-beam evaporated. After patterning the absorbers, absorber and stem mask material is removed, e.g., in a solvent bath and critical point drying.

Abstract: A service satellite for providing station keeping services to a host satellite has a body, and a gripping mechanism attached to the body. The gripping mechanism is adapted to attach to an interface ring extending from an external surface of the host satellite to form an interconnection between the host satellite and the service satellite through the externally extending interface ring. Attaching the gripping mechanism to the interface ring forms an interconnected unit having a combined center of mass. The service satellite has at least two movable thrusters and at least one controller. The at least one controller maintains the interconnected unit in a substantially stationary orbit by selectively orienting the two thrusters such that the thrust vectors from the two thrusters do not pass through the combined center of mass, and are each offset from the combined center of mass.

Abstract: An apparatus and method are provided for communicating over power lines. The apparatus includes a coupling modem that is situated between a power line and a device. The coupling modem is configured to demodulate a signal received from the power line into a sine signal and a cosine signal. The coupling modem is also configured to modulate a communicated bit stream received from the device into a transmitted signal in order to impose the transmitted signal onto the power line.

Abstract: A satellite system comprises first and second devices, one of the first and second devices being a satellite and the other one of the first and second devices being a device arranged to send signals to the satellite. A session key can be distributed in the satellite system by obtaining the session key at the first device, protecting the session key at the first device, based on a private key of the first device and a public key of the second device, and transmitting the protected session key from the first device to the second device. Replay detection information can be transmitted with the protected session key, for determining whether the session key has been transmitted previously.

Abstract: A nanostructure device is provided and performs dual functions as a nano-switching/sensing device. The nanostructure device includes a doped semiconducting substrate, an insulating layer disposed on the doped semiconducting substrate, an electrode formed on the insulating layer, and at least one polymer nanofiber deposited on the electrode. The at least one polymer nanofiber provides an electrical connection between the electrode and the substrate and is the electroactive element in the device.

Abstract: An aerogel and method of making the aerogel is disclosed. The aerogel is a polyimide/polyamide hybrid with a cross-linking agent that induces gelation.

Abstract: A protective coating for a graphite (Gr) containing fuel element used in a nuclear thermal propulsion system includes a first layer that is configured to resist hot hydrogen attacks. The first layer has a coefficient of thermal expansion that is higher than a coefficient of thermal expansion of the Gr containing substrate. The coating also includes a plurality of second layers located between the first layer and the substrate. The second layers are configured to mitigate the differences in coefficients of thermal expansion between the first layer and the substrate to minimize debonding and exposure of the substrate to hydrogen attack. Preferably, the protective coating can comprise an outermost first layer including zirconium carbide (ZrC), a second layer including niobium (Nb), a third layer including molybdenum (Mo), and a fourth layer including molybdenum carbide (Mo2C) located adjacent to the substrate.

Abstract: A modular apparatus for attaching sensors and electronics is disclosed. The modular apparatus includes a square recess including a plurality of cavities and a reference cavity such that a pressure sensor can be connected to the modular apparatus. The modular apparatus also includes at least one voltage input hole and at least one voltage output hole operably connected to each of the plurality of cavities such that voltage can be applied to the pressure sensor and received from the pressure sensor.

Abstract: Described herein are ground based subsystems, and related methods, for use in transmitting an optical feeder uplink beam to a satellite that is configured to receive the optical feeder uplink beam and in dependence thereon produce and transmit a plurality of RF service downlink beams within a specified RF frequency range to service terminals. Also described herein are space based subsystems of a satellite, and related methods, for use in transmitting a plurality of RF service downlink beams within a specified RF frequency range to service terminals. Beneficially certain embodiments eliminate the satellite to perform any RF frequency conversions upstream of a channelizer of the space based forward link subsystem on the satellite. Also described herein is space segment return link equipment, and related methods, for use in transmitting an optical feeder downlink beam to a ground based subsystem, as well as ground based return link equipment thereof.

Abstract: A method for preparing asymmetric 3,4?-(hexafluroisopropylidene) dipthalic anhydride (a-6FDA) and asymmetric 3,4?-(methylene)diphthalic anhydride (a-MDPA) from asymmetric 2,3,3?,4?-benzophenone dianhydride (a-BTDA). First, a-BTDA is converted to its corresponding N-alkyl or N-phenyl bisimides by reacting with either methylamine or aniline. The sequential addition of two trifluoromethyl (CF3) groups to the carbonyl unit of a-BTDA produce the corresponding bisimides of asymmetric 6FDA, which is hydrolyzed to the asymmetric 6F-tetracarboxylic acid followed by cyclodehydration to obtain asymmetric 6F-dianhydride (a-6FDA). Separately, the carbonyl unit of bisimides of a-BTDA is reduced to a methylene unit to afford the corresponding bisimides of asymmetric 3,4?-(methylene)diphthalic anhydride, which is hydrolyzed to the asymmetric methylene tetracarboxylic acid followed by cyclodehydration to obtain 3,4?-(methylene)diphthalic anhydride (a-MDPA).

Abstract: An imager is provided for viewing subcutaneous structures. In an embodiment of the invention, the imager includes a camera configured to generate a video frame, and an adaptive nonlinear processor. The adaptive nonlinear processor is configured to adjust a signal of the video frame below a first threshold to a maximum dark level and to adjust the signal of the video frame above a second threshold to a maximum light level. The imager further includes a display, configured to display the processed video frame.

Abstract: An aircraft comprising a fuselage defining a longitudinal axis and an interior compartment. Along the axis, in cross-section perpendicular to the axis, the compartment is enclosed by a floor, sidewall and ceiling structure. The aircraft further comprises an environmental control system comprising a conduit system through which a pressurized fluid is supplied, at least one first terminal disposed inside the compartment and in fluid communication with the conduit system, and a selectively inflatable and deflatable partition element. The partition element comprises at least one second terminal and is constructed such that it is inflatable from a deflated condition into an inflated condition by establishing a fluid communication between the second terminal and the first terminal. In the inflated condition the partition element completely closes the cross-section of the compartment, thereby dividing it into two portions, and in the deflated condition collapses and at least partially unblocks the cross section.

Abstract: A metal or ceramic component includes at least one multi-dimensionally structured connection portion, wherein the connection portion is intended for forming an adhesive bond to fiber-reinforced polymer laminate, and wherein the metal or ceramic component has a milliscale structure, in particular formed by anchoring elements, and a microscale structure on the connection portion and the anchoring elements, over which microscale structure an additional nanoscale structure is formed.

Abstract: Disclosed herein is a lighter-than-air (LTA) device and method of making the same. In an embodiment, the LTA device may include a membrane having a flexible substrate and an active material disposed thereon, wherein the active material is configured to controllably change the surface area of at least a portion of the substrate when an electrical stimulus is applied to the active material.