Abstract: The system and method of retractable solar arrays for underwater vehicles. In some cases, the retractable solar arrays for underwater vehicles contain anti-biofouling mechanisms. The retractable solar arrays may extend in a linear or a fan-like manner. In some cases, the solar array may be wrapped around the outside of the underwater vehicle or within a cylindrical housing. In some cases the solar array is a single flexible member with a series of connected panels.

Abstract: A method of making GaP window slabs having largest dimensions of greater than 4 inches and GaAs IR window slabs having largest dimensions of greater than 8 inches, includes slicing and dicing at least one smaller GaAs or GaP single crystal boule, which can be a commercial boule, to form a plurality of rectangular slabs. The slabs are ground to have precisely perpendicular edges, which are polished to be ultra-flat and ultra-smooth, for example to a flatness of at least ?/10, and a roughness Ra of less than 10 nanometers. The slab edges are then aligned and fused via optical-contacting/bonding to create a large GaAs or GaP slab having negligible bond interface losses. A conductive, doped GaAs or GaP layer can be applied to the window for EMI shielding in a subsequent vacuum deposition step, followed by applying anti-reflection (AR) coatings to one or both of the slab faces.

Abstract: According to the present disclosure there is provided a duct arrangement for influencing fluid flow, the duct arrangement comprising: a duct section arranged to receive a fluid flow therethrough, the duct section defining a first direction through the duct section from a fluid inlet end to a fluid outlet end; a rotor housed in the duct section, the rotor comprising one or more rotor blades; and a vortex generator surface housed in the duct section, the vortex generator surface arranged to induce vortices in the fluid flow through the duct section.

Abstract: A barrel for a launching device for launching projectiles with a propellant charge is arranged with a cross-section in the form of a curve of constant width. A launching device and a method for firing a rotation-stabilized projectile from a barrel are also provided.

Abstract: According to the present disclosure there is provided a liquid flow influencing duct arrangement comprising: a first duct section arranged to receive a liquid flow therethrough, the first duct section defining a first direction through the first duct section from a liquid inlet end to a liquid outlet end; a second duct section defining a second direction through the second duct section from a liquid inlet end to a liquid outlet end, the second duct section comprising a vortex generator surface, wherein the vortex generator surface is arranged to induce vortices in the liquid flow through the first duct section, wherein the duct arrangement further comprises a rotor housed in one of the duct sections.

Abstract: A laser transmission assembly for shearography and related systems utilizing transmissive geometric phase plate pairs in place of Risley prism pairs or movable mirrors therein. Transmissive geometric phase plates provide for a system that is more compact than systems utilizing mirrors or Risley prism pairs while maintaining or improving the adjustability of the system and further offering beamshaping to provide desired illumination patterns.

Abstract: Techniques for reducing a likelihood of detection of an imaging system by another imaging system are provided. For example, a mechanism may be used to interrupt an optical path between pulse biased thermal sensors and an aperture of the system when the pulsed biased thermal sensors are pulse biased. For example, emissions may be directed to a beam dump. Other techniques may include a mechanism for linearly moving the thermal sensor array or rotating a mirror.

Abstract: A compressor module (200) wherein the compressor module (200) defines a working fluid flow duct (60) between a compressor module inlet (210) and a compressor module outlet (214). The compressor module comprises: a first heat exchanger (37) and a compressor rotor stage (24) each provided in the working fluid flow duct (60). The first heat exchanger (37) is provided in flow series between the compressor module inlet (210) and the compressor rotor stage (24). The compressor stage (24) is provided in flow series between the first heat exchanger (37) and the compressor module outlet (214). The first heat exchanger (37) is defined by a wall (226) having an external surface (282) which is located in the working fluid flow duct (60). There is provided a heat sink unit (236) which defines a portion (240) of the working fluid flow duct (60) in flow series between the compressor rotor stage (24) and compressor module outlet (214).

Abstract: A multi-bit, asynchronous e-fuse macro, the macro comprising: the following inputs: an input output enable, a power on reset, a write address, an input write enable, a ground clamp enable, and a write clock; a plurality of e-fuse bits; a supply voltage configured to allow programming at least one of the e-fuse bits; at least one fuse output; and self-timing and control circuitry configured to perform signaling, wherein each of the inputs is in electrical communication with said e-fuse macro.

Abstract: An oscillation system includes an oscillation circuitry configured to cause at least one motor of a first set of motors to provide an oscillation of a user-input device in at least one axis of the user-input device. The oscillation may be triggered in response to an input from at least one sensor, the user-input device for operating an aircraft control system of an aircraft. The oscillation circuitry is configured to operate independently from a resistive force circuitry. The resistive force circuitry is to provide a resistive force to the user-input device, using the at least one motor of the first set of motors.

Abstract: Techniques to provide compression and/or decompression. A method includes obtaining a first set of control points specifying a first set of compression ratios corresponding to respective first regions of a compression domain, and minimum and maximum uncompressed values within the compression domain. The method can further include scaling the first set of control points based on the minimum and maximum uncompressed values to obtain a scaled set of control points, wherein a first scaled control point is located at the minimum uncompressed value, and a last scaled control point is located at the maximum uncompressed value. The method can further include adjusting at least one scaled control point such that a first slope does not exceed 1. The method can further include compressing or decompressing between the compression domain and a range of compressed values, wherein a respective compression ratio corresponds to a respective slope of the set of slopes.

Abstract: A battery assembly includes a first plurality of battery cells, a second plurality of battery cells, and a switch between the first plurality of battery cells and the second plurality of battery cells. In an example, the first plurality of battery cells, the switch, and the second plurality of battery cells are connected in series to a load. In an example, the first plurality of battery cells, the second plurality of battery cells, and the switch are within an enclosure, which is within a pressure regulated section of an aircraft. The load may be external to the enclosure. The battery assembly further includes a controller configured to open the switch and the disconnect the first plurality of battery cells from the second plurality of battery cells, in response to an air pressure proximal to the first and second pluralities of battery cells falling below a threshold level.

Abstract: A battery assembly includes an enclosure including a plurality of battery cells, and a sensor within the enclosure. The sensor is configured to measure a parameter within the enclosure, and generate a sense signal. The battery assembly further includes a processor within the enclosure, wherein the processor is configured to process the sense signal and generate information associated with the sense signal. A first communication link is configured to transmit, from the enclosure to a system that is external to the enclosure, a discrete signal indicative of whether the sense signal indicates a fault condition. A second communication link is configured to transmit, from the enclosure to the system, a digital signal including the information. Thus, transmitting the discrete signal over the first communication link and the information associated with the sense signal over the second communication link provides redundancy and improves reliability of the battery assembly.

Abstract: According to the present invention there is provided a polarisation converter comprising: a first element array layer extending in a plane comprising a first array of spaced apart electrically conductive dipole elements: a second element array layer extending in a plane comprising a second array of spaced apart electrically conductive dipole elements: a dielectric layer extending in a plane separating the first element array layer and the second element array layer, each element array layer having a first and second axis parallel to the plane of the respective element array layer, the first axis and second axis being perpendicular axes, wherein: one or both of the element array layers exhibits an anisotropic spatial property. An antenna system, vehicle and method of manufacturing a polarisation converter are also provided.

Abstract: The disclosure relates to methods for determining damage of an endless track of a tracked vehicle that comprises at least one track assembly comprising said endless track disposed in its longitudinal extension around a set of wheels. Said track comprises a wire configuration arranged within said track configured to run in the longitudinal extension around said track. Said wire configuration comprises one or more individual wires arranged to run within said endless track so that a set of wire portions are running in said longitudinal extension. The method comprises: receiving, from at least one sensor device, via measuring connectors, measurement information associated with electrical properties of wire portions of said wire configuration; based on the information received from said at least one sensor device, determining electrical properties of said wire portions; and, based on the determined electrical properties, determining whether there is a damage to the endless track.

Abstract: Disclosed is an arrangement for feeding ammunition to a weapon. The weapon is mounted to an elevation device arranged to allow elevation movement of the weapon about an elevation axis. The arrangement includes a feeding chute connected at one end to the weapon. The feeding chute includes a set of elements assembled together in a stacked configuration. The set of elements is arranged about a shaft configured to be concentrically arranged relative to the elevation axis so as to allow movement of individual elements of the set of elements about the shaft in connection to elevation movement of the weapon about the elevation axis. The invention also relates to a vehicle with an arrangement according to the present invention.

Abstract: An antenna assembly includes an antenna feed configured to receive a signal over a wide bandwidth, a ground plane, and an antenna element. The antenna element includes first and second conductive dipole arms each in planar alignment with a surface of the ground plane and adjacent to each other. The antenna assembly further includes a conductive wall (“H-wall”) in electrical communication with the ground plane and having an end adjacent to, and physically separate from, the second conductive dipole arm, where an axial length of the H-wall being orthogonal to the ground plane, and a resistive surface having an attenuation effect on the reflected signal from the ground plane.

Abstract: An antenna assembly includes at least one conductive dipole arm and an adjacent conductive wall (“H-wall”), which enables efficient radiation from the conductive dipole arm without added losses. A single-ended antenna feed is configured to receive a single-ended signal. The antenna assembly further includes a ground plane and a conductive dipole arm in planar alignment with a surface of the ground plane. The conductive wall is electrically coupled with the ground plane and has an end adjacent to, and physically separate from, the conductive dipole arm, an axial length of the H-wall being orthogonal to the ground plane. The antenna assembly further includes a feedline electrically coupled with the conductive dipole arm and the single-ended antenna feed.

Abstract: A system for enhancing a coupling laser beam to create a larger beam radius thus increasing sensitivity inside the system. The system includes a coupling laser source to emit a coupling laser defining a first power level. The system also includes a resonant optical cavity that is optically aligned with the coupling laser source and the probe laser source. The resonant optical cavity enhances the coupling laser to a second power level that is greater than the first power level inside of the resonant optical cavity. The power increase of the coupling level also increases the sensitivity of the atomic receiver system by increasing the diameter of the coupling laser inside of the resonant optical cavity. The system also includes at least one photodetector positioned outside of and optically aligned with the resonant optical cavity for monitoring a resonance condition of the coupling laser circulating within the resonant optical cavity.

Abstract: A computer-implemented method of training a machine learning, ML algorithm to control spin-stabilized steerable projectiles is described. The method comprises: obtaining training data including respective policies and corresponding trajectories of a set of spin-stabilized steerable projectiles including a first projectile, wherein each policy relates to steering a projectile of the set thereof towards a target and wherein each corresponding trajectory comprises a series of states in a state space of the projectile (S2001); and training the ML algorithm comprising determining relationships between the respective policies and corresponding trajectories of the projectiles of the set thereof based on respective results of comparing the trajectories and the targets (S2002).