Abstract: An electroacoustic transducer array 110 is described. The electroacoustic transducer array 110 comprises a first electroacoustic transducer 40A comprising a first active element 41A and a second electroacoustic transducer 40B comprising a second active element 41B. The electroacoustic transducer array 110 comprises an acoustic coupling layer 43 arranged to acoustically couple, in use, the first active element 41A and the second active element 41B to a transmission medium. The electroacoustic transducer array 110 comprises a first cavity 42A arranged between the first active element 41A and the acoustic coupling layer 43 to receive a first fluid; and/or a second cavity 42B arranged between the second active element 41B and the acoustic coupling layer 43 to receive a second fluid. In this way, acoustic coupling of the electroacoustic transducer array 110 and the transmission medium is improved.

Abstract: This invention relates to a parachute sea anchor system deployable from a payload tube. There is provided a parachute sea anchor system suitable for launch from a vessel comprising at least one payload tube, said payload tube, comprising a payload canister, which comprises a parachute sea anchor, wherein said parachute sea anchor comprises a buoy tethered thereto, wherein said payload canister is attached to said vessel.

Abstract: A head mounted display system for use on a watercraft is disclosed. The head mounted display system comprises circuitry to determine orientation information of a head mounted display system relative to the watercraft and a display configured to superimpose graphical information over objects in a field of view of at least one eye of a user of the head mounted display system. The graphical information is based on sensor data and the orientation information of the head mounted display. The sensor data is provided by at least one data source associated with the watercraft.

Abstract: According to an aspect of the invention, there is provided a fuze arming system for a munition, comprising: an arming circuit arranged to detect a setback event and, in response to the setback event, generate a signal indicating that an arming event has occurred, wherein the arming circuit comprises a sensor configured to produce a graduated output when the setback event occurs, and fuze arming system is arranged to use that graduated output.

Abstract: A blast attenuation device for a gun tube. The blast attenuation device has a first wall section which defines a first chamber, which extends from an inlet end having an inlet aperture to an outlet end having an outlet aperture. The blast attenuation device also has a second wall section which defines a second chamber, which extends from an inlet end having an inlet aperture to an outlet end having an outlet aperture.

Abstract: A signal transmitting device is provided for communicating with an aircraft in the vicinity of a landing area. The signal transmitting device is configured to receive a signal from the aircraft and further configured to transmit a return signal to the aircraft automatically upon receipt of the signal. The return signal comprises information regarding the landing area.

Abstract: An arrangement for influencing liquid flow comprises a first section selectively configurable to provide a vortex generator surface to induce vortices in the liquid flow. The arrangement further comprises a second section, wherein the first section and second section are movable relative to one another to provide the vortex generator surface.

Abstract: A control system for assisting a pilot to control an aircraft operating under control of an active inceptor, the control system comprising: a receiver for receiving pilot-inputs on an active inceptor, an instruction generator to generate an instruction, the instruction based on an external signal associated with the geographical location of the aircraft; a tactile cue generator to generates a tactile cue which causes the active inceptor to move from a nominal position to a first offset position within a predetermined time period in response to the instruction.

Abstract: A support structure for manufacturing a pressure vessel, the support structure configured to be carried on a supporting substrate, the support structure comprising a first segment support structure nestable within, and moveable relative to, a second segment support structure, wherein the first segment support structure is configured to be raised and lowered relative to the second segment support structure to thereby raise and lower the first segment relative to the substrate, and the first segment support structure is configured to move between a nested position within the second segment support structure to a position spaced apart from the second segment support structure across a surface of the substrate.

Abstract: An interface node for enabling a robotic arm to be used as a reconfigurable fixture for vehicle manufacture is described. The interface node comprises an attachment element for attaching the interface node to the robotic arm. The interface node also comprises a first locating element, the first locating element comprising a flat surface wherein the flat surface is suitable for locating a first feature of a first component wherein the first feature comprises a face of the first component. The interface node further comprises a wall extending from and substantially around the flat surface, the wall connecting the flat surface to the attachment element wherein the wall defines a second locating element, the second locating element suitable for locating a second feature of a second component, which may or may not be the same.

Abstract: In some examples, an apparatus for optical underwater data transmission comprises an optical transmitter configured to generate an optical signal for a short range underwater optical communications channel, wherein the optical transmitter comprises a source of electromagnetic radiation configured to generate an optical signal with a selected wavelength.

Abstract: A signal from a mobile communication device (102) of an unmanned aerial vehicle (103) is received, via cellular network communication, by each of a plurality of cellular network base stations (106, 107, 108). A position of the unmanned aerial vehicle (103) is determined based on a triangulation operation performed using the signal received by the cellular network base stations (106, 107, 108). Vehicle navigational data derived from the position determination is used to determine that a navigation assistance notification should be communicated to a notification receiver (102, 114) and, in response, communication of the navigation assistance notification to the notification receiver (102, 114) is initiated.

Abstract: A mobile communication device (102) of a vehicle (103) is associated with a navigation system (202). Vehicle navigational data derived from the navigation system (202) is received, via cellular network communication, from the mobile communication device (102) of a vehicle (103). The vehicle navigational data is used to determine that a navigation assistance notification should be communicated to the mobile communication device (102) and, in response, communication of the navigation assistance notification to the mobile communication device (102) is initiated.

Abstract: A method of performing analogue to digital conversion of an analogue input signal. The method comprises: generating a first laser pulse train having a first wavelength; generating a second laser pulse train having a second different wavelength; modulating, using an interferometric modulator, the first laser pulse train and the second laser pulse train on the basis of the analogue input signal, wherein the interferometric modulator is configured such that its response to the first laser pulse train is not in phase with its response to the second laser pulse train; determining, on the basis of the modulated first laser pulse train and the modulated second laser pulse train, a voltage of the analogue input signal; and generating a digital signal indicative of the determined voltage.

Abstract: In some examples, an underwater imaging apparatus comprises a source of electromagnetic radiation configured to generate a short-range illuminating beam at a selected wavelength, and an image sensor for generating image data representing a scene or object to be illuminated by the illuminating beam, the image sensor sensitive to the selected wavelength.

Abstract: An unmanned vehicle (20) for relaying radio frequency signals in a tactical communications network is described. The unmanned vehicle comprises a processor (22) arranged to receive the location of a first asset (40a); select a relay site (30) from at least one relay site; and control the unmanned vehicle to move to the selected relay site, wherein at the selected relay site, communication between the first asset and the unmanned vehicle is enabled. The unmanned vehicle also comprises a receiver for receiving data from the first asset; and a transmitter for transmitting the data to a second asset (40b, 20, 10). A control unit (60) for an unmanned vehicle, a tactical communications network comprising a plurality of unmanned vehicles, and a method of relaying signals in a tactical communications network using an unmanned vehicle are all also described.

Abstract: There is provided an apparatus for pulse charging of a load capacitor, the apparatus comprising: a ferrous cored transformer having a primary winding and a secondary winding; a primary circuit connected to the primary winding; a secondary circuit connected to the secondary winding, the secondary circuit comprising the load capacitor; and an uncoupled inductance in the primary circuit or the secondary circuit, the uncoupled inductance reducing the coupling coefficient between the primary circuit and the secondary circuit.

Abstract: A video processing system (100) comprises at least one controller (102) configured to receive a plurality of video data from a respective plurality of video data sources (106, 208). The system can assign one of a plurality of hierarchical display layers to each of the plurality of video data, and generate an output video for display, the output video comprising at least a portion of each of the plurality of video data layered according to the assigned hierarchical display layers. The plurality of hierarchical display layers is based on a respective plurality of safety/security levels defined in a safety/security standard.

Abstract: A drive arrangement for manipulating a vehicle control surface, comprises: a first drive; a second drive; an output member for connecting to the vehicle control surface; first engaging means for selectively engaging and disengaging the first drive and the output member; and second engaging means for selectively engaging and disengaging the second drive and the output member, wherein the first drive and the second drive are mounted on bearings.

Abstract: According to some examples, an energy harvesting assembly for a projectile comprises an inlet provided at the tip of a casing of the projectile, multiple outlets provided circumferentially around an outer surface of the casing proximate the tip, and an airflow channel structure extending from the inlet in a generally axial direction through a turbine to the multiple outlets.