Abstract: A cavity system, comprising: a cavity (2) comprising a cavity opening; and an acoustically reflective structure (18, 20) located at least partially within the cavity (2), the acoustically reflective structure (18, 20) comprising one or more acoustically reflective surfaces (24, 26, 30, 32), each acoustically reflective surface (24, 26, 30, 32) being oblique to a plane of the cavity opening (27). The one or more acoustically reflective surfaces (24, 26, 30, 32) may be arranged to reflect incident acoustic waves out of the cavity opening while avoiding reflection into a region (48) at or proximate to a leading edge (14) of the cavity (2).

Abstract: This invention relates to improvements in and relating to ice pigging, and comprises a flowable slush of frozen particles for ice pigging a pipework, comprising, an aqueous liquid medium, a multiplicity of frozen particulates of said aqueous liquid medium, a freezing point depressant, selected from a hydroxide ion, said hydroxide ion present in the range of less than 10 wt %.

Abstract: A method to detect a hands off status of a user input device is disclosed. The method comprising filtering a sensed force, acting on the user input device, using a first lag filter to provide a first output, the lag filter comprising a first lag time constant. Filtering the sensed force using a second lag filter, substantially in parallel with the first filter, to provide a second output, the second lag filter comprising a second lag time constant greater than the first lag time constant. Comparing with a first threshold value, in a first comparison, a magnitude of a difference between the first output and the second output. Comparing with a second threshold value, in a second comparison, a magnitude of the second output. Designating the user device to have a hands off status based on the first comparison and the second comparison.

Abstract: There is disclosed an aircraft configured to collect air data, the aircraft comprising: a wing structure; a forebody, forward of the wing structure; an afterbody, backward of the forebody; a skin covering the wing, the forebody and the afterbody; at least one recess formed at the skin, the recess being configured to affect the pressure of air flowing at the recess; at least one ambient sensor port for measuring ambient air pressure at the skin; and at least one recess sensor port for measuring the air pressure at the recess.

Abstract: A method to obtain total compensation force information of a user input device is disclosed. The method comprising obtaining velocity information of a portion of the user input device. Obtaining acceleration information of the portion of the user input device. Obtaining damping force information force based on the velocity information. Obtaining inertial compensation force information based on the acceleration information. Combining the damping compensation force and inertial compensation force to provide the compensation force information of the user input device.

Abstract: An assembly method comprising: providing a digital model of an aircraft airframe (200), the digital model comprising digital models of component parts (202, 204) of the airframe (200); providing the component parts (202, 204), each comprising one or more predrilled fastener holes; fixing a first component part (202a) to a support structure (1102); fixing a second component part (204a) to an end effector (1112) of a robot arm (1110); using the airframe digital model, controlling the robot arm (1110) to move the second component part (204a) relative to the first component (202a) as specified in the airframe digital model to cause one or more predrilled holes in the second component (204a) part to align with one or more predrilled holes in the first component part (202a); and attaching the second component part (204a) to the first component part (202a) using fasteners through the aligned predrilled holes.

Abstract: There is provided a sacrificial sensor configured to be coupled with a part and provide an indication of damage in the part, wherein an electrical property of the sacrificial sensor is configured to change as the sacrificial sensor is damaged to indicate damage to the part.

Abstract: A robotic system comprising: a multi-axis robot; one or more sensors located on the multi-axis robot; a damping system configured to apply a resistive force to the multi-axis robot, thereby to resist movement of the multi-axis robot; and a controller coupled to the one or more sensors and the damping system, the controller being configured to: receive sensor measurements from the one or more sensors; and control, based on the received sensor measurements, the damping system thereby to control the resistive force applied by the damping system to the multi-axis robot.

Abstract: There is disclosed a fluid sensor for measuring the pressure of a fluid, the fluid sensor comprising: a surface; a recess formed at the surface, the recess being configured to affect the pressure of the fluid flowing at the recess, at least one ambient sensor port for measuring ambient fluid pressure at the surface, and at least one recess sensor port for measuring the fluid pressure at the recess.

Abstract: A system and method of positioning a set of vehicles (102) with respect to an object (104) and a set of targets (106). Embodiments can generate (302) an isovist using data obtained from at least one sensor associated with the object and use it to compute (304) an estimated position of each target with respect to the object. Embodiments can compute (306) a plurality of positions for each vehicle based on the estimated positions of the targets, with each position having an associated value representing a number of the targets at their estimated positions that are within a predetermined proximity of the vehicle at that position. Embodiments can select (308) a subset of the positions based on the associated values, and position (310) the set of vehicles based on the selected subset of the positions.

Abstract: A method is provided for adjusting a luminance profile of an image displayed on a look-through display to a user. The method comprises: determining a field of view of the user based on a spatial configuration of the user's head. Determining one or more lighting conditions in the field of view. Adjusting the luminance profile for the image based on the field of view, wherein, as a result of the adjusted luminance profile, the image is reconciled with the field of view.

Abstract: A method of producing at least part of a structural frame of a vehicle, the method comprising: providing a support structure (300), the support structure (300) comprising: a plurality of elongate members (301); and one or more retaining members (208) configured to retain the elongate members (301); mounting a plurality of first structural components (206) to the support structure (300) by coupling the first structural components (206) to the elongate members (301) such that each first structural component (206) occupies a different respective position along the elongate members (301); and attaching a plurality of second structural components (204) to the first structural components (206), thereby coupling together the first structural components (206) to form the at least part of the structural frame of a vehicle.

Abstract: The present invention provides a sabot (8) comprising a first material structure (12, 14) and a second material structure, wherein the first material structure is a lattice and wherein the second material structure is a solid. A munition (100) and a method of manufacturing a sabot are also provided.

Abstract: A system comprises a camera for capturing an image, at least one processor and at least one memory, the at least one memory storing instructions configured to cause the processor to: obtain an image of a scene captured using the camera, the scene comprising a footprint of a user of the system; identify the footprint in the image; identify a first plurality of reference points each having a fixed position relative to the footprint in the image; identify a second plurality of reference points each having a fixed position relative to a three-dimensional model of the user's foot constructed based on at least one known dimension of the user's foot; determine a transformation matrix by mapping the second plurality of reference points of the three-dimensional model to the first plurality of reference points; and determine, based on the transformation matrix, a three-dimensional position of the camera relative to the footprint in the scene at the time of capturing the image.

Abstract: According to a first aspect of the present invention, there is provided a fuse system (22) for a munitions projectile, the system comprising: a first electro-optic transmitter (24); a first electro-optic receiver (30); the first electro-optic transmitter (24) being arranged to receive electrical power, and to use that received electrical power to transmit an optical signal (28) to the first electro-optic receiver (30); the first electro-optic receiver (30) being arranged to receive the optical signal (28), and to use that received optical signal (28) to transmit electrical power to an element (34) of the fuse system (22) connected to the first electro-optic receiver (30).

Abstract: A helmet mounting for optical combiner (50) for a HMD has a pivoted mounting arm (60) for the optical combiner to be movable between an operational position in a line of sight, and a retracted position displaced out of the line of sight. A translation mechanism (100) provides translation of the optical combiner along the line of sight. A driving lever (30) causes the displacement of the mounting arm between the line of sight and the retracted position, and with a second motion of the lever, causes the translation of the optical combiner. By having the same lever coupled to both the mounting arm and the translation mechanism, the relatively complex combination of displacement and translation movements of the optical combiner can be reduced to a simpler movement, easier for a user such as a pilot to use even when under stress in a busy and cramped cockpit environment.

Abstract: According to some examples, a non-incendiary projectile comprises a housing defining an internal cavity, and an energy harvesting structure comprising a first part and a second part, the first part provided on an inner surface of the housing, the second part provided in the internal cavity, the second part further comprising a rotation damping system configured to regulate a rate of rotation of the second part in a rotational direction about a flight axis defined by the housing.

Abstract: An optical system (100) comprising: a transmitter module (102) configured to transmit a sequence of optical pulses (300), each optical pulse in the sequence (300) having a different magnitude to each other optical pulse in the sequence (300); a receiver module (104) comprising one or more optical signal detectors, the receiver module (104) configured to receive the sequence of optical pulses (300) transmitted by the transmitter module (102); and one or more processors (110) configured to process the sequence of optical pulses received by the receiver module (104) to select an optical pulse from the received sequence of optical pulses (400) based on one or more predetermined criteria. The one or more predetermined criteria include a criterion that the selected optical pulse does not saturate the one or more optical signal detectors.

Abstract: A folded optical arrangement for use in a look-through display to transmit an image from an image plane to a user's eye, the arrangement providing a folded optical transmission path and comprising: an optical system having a first optical element comprising a first plurality of optically powered surfaces; and a second optical element comprising at least one optically powered surface, the optical system configured to receive light forming the image from an image source, and to focus the light to have an apparent optical focus between a predetermined distance and optical infinity and output the light; wherein the first plurality of optically powered surfaces and the at least one optically powered surface of the second optical element are arranged to define a plurality of interfaces along the folded optical path and wherein a refractive index change at each interface is predetermined to control the direction of light passing through the or each interface; and wherein one surface of the first optical element and

Abstract: This invention relates to a combination of a gun having a rifled barrel and a round of enhanced performance ammunition, and to a projectile for use in the combination. The invention is especially, but not exclusively related to a projectile with a nominal calibre, for use in a rifled barrel, the projectile comprising: an elongate metal core, a ceramic tip with a Vickers Hardness greater than said metal core, said ceramic tip abutted with one end of the elongate metal core, wherein a deformable jacket or deposited coating, surrounds the elongate metal core and ceramic tip, such that said jacket or coating defines the nominal calibre of said projectile.