Abstract: The invention relates to a method of determining the relative positions of components of a munitions system, the munitions system comprising a first component (331) and at least one second component (333). The method comprises monitoring the output of a resonant circuit (305) provided on a first component (331), the resonant circuit (305) having a resonant frequency, detecting a change in the output due to a change in the resonant frequency caused by a change in the relative positions of the first component (331) and the at least one second component (333), and using the detected change to determine that the at least one second component (333) has moved relative to the first component (331).

Abstract: An acousto-optic device is disclosed. The device comprises: an optically transmissive element to receive a beam of light at an input surface, the beam being received from a direction defining an optical axis; a set of acoustic transducers spaced around the element; and a controller operable to activate the transducers to generate an acoustic wave travelling through the device to intersect with the optical axis. The controller is further operable to selectively activate a first subset of the set of transducers such that the acoustic wave propagates in a selected direction. Each of the set of acoustic transducers is differently orientated such that the selected direction is controllable through the selection of first subset of transducers from the set of transducers, and the device is thereby operable to control the direction in which the beam of light is deflected in two dimensions. A method of operating the device is also disclosed.

Abstract: An imaging device includes: an array of liquid crystal cells, each liquid crystal cell providing a respective phase shift to electromagnetic radiation passing through the liquid crystal cell; control electronics for controlling the phase shifts provided by each of the liquid crystal cells; a detector; and an image processor for generating an image from electromagnetic radiation detected by the detector. The array of liquid crystal cells form a plurality of patches; and the control electronics is configured to control the phase shifts of the cells of each patch to form each patch into a respective lens that focuses electromagnetic radiation towards the detector such that the plurality of patches form an array of lenses.

Abstract: There is disclosed a device for determining a strength of an oscillating electric field. The device comprises an absorber to absorb radiation at the frequency of the oscillating electric field, and a thermal insulator transparent to radiation at the frequency of the oscillating electric field, which thermal insulator is arranged to thermally insulate the absorber. The device also comprises a first temperature sensor arranged to measure the temperature of the absorber, and a second temperature sensor arranged to measure the temperature external to the thermal insulator. Methods of measuring electric field using such a device, and methods of calibrating such a device, are also disclosed.

Abstract: Method of and system for monitoring mechanical fatigue of a complex weapon system. First, data representing a movement of the complex weapon system is acquired. On the basis of the acquired data, a measure of mechanical fatigue damage to the complex weapon system arising from the movement is calculated. On the basis of that calculated measure, a cumulative total of the mechanical fatigue damage accrued by the complex weapon system is updated to account for the mechanical fatigue damage arising from the movement.

Abstract: A method of actuating an article using a servo actuation system is disclosed. The system comprises a motor, a controller and an inverter. The controller comprises a position controller, a velocity controller and a current controller; the position controller outputs velocity demands to the velocity controller, the velocity controller outputs current demands to the current controller, and the current controller outputs voltage demands to the inverter. The inverter outputs inverted voltage demands to the motor. The method comprises: determining a parameter downstream of the inverter; calculating a limiting value from the parameter and a defined supply power limit; and applying the limiting value in the controller to ensure that the power drawn by the servo actuation system remains within the defined supply power limit.

Abstract: A safety assembly for use with a laser-directed energy weapon is disclosed. The assembly comprises a control system comprising a photodetector and a processing unit; and an optical device configured to attach to a target such that, when attached, the optical device provides a light beam to the photodetector. The processing unit is arranged to compare the received light beam against one or more predetermined attributes, and to permit the laser-directed energy weapon to fire only when the received light beam is determined to have the one or more attributes.

Abstract: The present disclosure comprises an evaporative cooling assembly (200) for cooling an apparatus (220), and a method for cooling an apparatus (220). The evaporative cooling assembly comprises a refrigerant tank (202), the refrigerant tank (202) containing refrigerant (204). The apparatus also comprises a first evaporator (210) configured to be positioned proximal to the apparatus (220), and a second evaporator (216) positioned to cool the refrigerant tank (202). Each of the first evaporator (210) and the second evaporator (216) are in fluid communication with the refrigerant tank (202), and the second evaporator (216) is positioned downstream of the first evaporator (210). The method for cooling a heated apparatus (220) comprises passing a refrigerant (204) from a refrigerant tank (202) to a first evaporator (210), which is located proximal to the apparatus (220).

Abstract: A cover for an intake of an air-breathing engine in a missile is disclosed. The cover comprises a motive arrangement operable to move from a first configuration in which the cover is lockable to a missile, to a second configuration in which the cover is pushed outwardly from the missile. In the first configuration, the surface of the cover is flush with the surface of the missile and the motive arrangement is located inwardly of the cover surface. A missile provided with such a cover is also disclosed.

Abstract: A method of controlling a self-propelled flying device that seeks a target. A desired time to reach the target is obtained. The position of the target is acquired. A bias value is calculated, and the flight of the device towards the target is adjusted for a period of time using the bias value. The bias value is calculated so that the device reaches the target at the desired time.

Abstract: A cover for an intake of an air-breathing engine in a missile is disclosed. The cover comprises a closure for closing the inlet so as to prevent ingress of debris; and a fastening attachable to an aircraft-mounted launcher and configured such that the cover remains attached to the aircraft on launch of the missile.

Abstract: There is disclosed a missile comprising an outer skin, an electronics unit, and a thermal link between the electronics unit and the outer skin. The thermal link comprises a jumping drop vapour chamber arranged such that, when the outer skin is at an elevated temperature relative to the electronics unit, the electronics unit is thermally insulated from the outer skin; and such that, when the outer skin is at a lower temperature relative to the electronics unit, the electronics unit is thermally linked to the outer skin.

Abstract: An inductive power transfer system (1) for coupling a power source to a load across an air gap (11) is disclosed. The system (1) comprises a primary unit (3) associated with a host platform and a secondary unit (5) arranged to receive power transmitted inductively from the primary unit (3). The primary unit (3) includes a phase detection circuit (21) configured to detect phase changes in a signal in the primary unit (3) indicative of changes in an operating condition within the secondary unit (5), and a drive circuit (17). The drive circuit (17) is configured to adjust the power level transmitted to the secondary unit (5) depending on the detected phase.

Abstract: An aircraft comprises a weapons bay, the weapons bay comprising a cavity having an opening through which stores may be deployed, and a door assembly for exposing/closing the opening of the cavity. A first store is held in the cavity via a launcher and a first structure is disposed inside the cavity, for controlling the aero-acoustic environment. The first structure for controlling the aero-acoustic environment is removeably mounted in the weapons bay, such that if the first store is exchanged for a second, different, store, the structure for controlling the aero-acoustic environment may be unmounted from the weapons bay and removed, to be exchanged for a second, different, structure for controlling the aero-acoustic environment.

Abstract: There is disclosed a device for determining a strength of an oscillating electric field. The device comprises an absorber to absorb radiation at the frequency of the oscillating electric field, and a thermal insulator transparent to radiation at the frequency of the oscillating electric field, which thermal insulator is arranged to thermally insulate the absorber. The device also comprises a first temperature sensor arranged to measure the temperature of the absorber, and a second temperature sensor arranged to measure the temperature external to the thermal insulator. Methods of measuring electric field using such a device, and methods of calibrating such a device, are also disclosed.

Abstract: An imaging device and a method of imaging are disclosed. The device includes an array of liquid crystal cells, each providing a phase shift to electromagnetic radiation passing through the cell; control electronics for controlling the phase shifts provided by each of the liquid crystal cells; a detector; and an image processor for generating an image from electromagnetic radiation detected by the detector. The array of cells form a plurality of patches; and the control electronics is configured to control the phase shifts of the cells of each patch to form each patch into a respective lens that focuses electromagnetic radiation towards the detector such that the patches form an array of lenses. A method of imaging is also disclosed.

Abstract: A circuit assembly (200) is disclosed comprising a substrate (210) and conducting layers (250) on opposing sides of the substrate (210), there being at least one via (220) through the substrate (210), which via (220) forms a conductive path between the conducting layers, wherein the substrate (210) is a foam substrate, and wherein the via (220) is provided with a solid dielectric lining (270) plated with a conducting material (250).

Abstract: Monopulse radar apparatus is disclosed. The apparatus comprises a digital processor and an antenna having a plurality of receive channels through which signals received by the antenna are passed to the processor. Each receive channel includes an analogue to digital converter, and the processor is arranged to calculate sum and difference signals from the signals received through each receive channel. The processor is also arranged such that, in the event that a malfunction is detected in one of the plurality of receive channels, compensated sum and difference signals are calculated by the processor using the signals from the remaining, functioning receive channels.

Abstract: A mission planning method for use with a weapon is disclosed. The method comprises: obtaining a first training data set describing the performance of the weapon; using the first training data set and a Gaussian Process (GP) or Neural Network to obtain a first surrogate model giving a functional approximation of the performance of the weapon; and providing the first surrogate model to a weapons system for use in calculating a performance characteristic of the weapon during combat operations.

Abstract: A cover for an intake of an air-breathing engine in a missile is disclosed. The cover comprises a motive arrangement operable to move from a first configuration in which the cover is lockable to a missile, to a second configuration in which the cover is pushed outwardly from the missile. In the first configuration, the surface of the cover is flush with the surface of the missile and the motive arrangement is located inwardly of the cover surface. A missile provided with such a cover is also disclosed.