Qinetiq Limited

Quinetiq Limited

Jonathan Geoffrey Gore

Mark Gregory Maylin

Richard Carson McBride

Ahmed Yehia Amin Abdel Rahman

George Jiri Tomka

Fiona Louise Lowrie

Christopher Robert Lawrence

Stuart John Eaton

Adrian Robert Bowles

Abdul-Salam Kaddour

Jeremy Leonard Clive Ludlow

Ahmed Yehia Amin Abdel-Rahman

Adam Daykin

James Carl Milne

Derek Atkinson

Patrick T Squire

Richard Carson Mcbride

David Gordon Madgwick

Ahmed Yehia Amin Abdel Rahaman

A multistage flextensional transducer includes at least one inner elongate driver member within and mechanically coupled to an inner shell that is nested within an outer shell; the inner shell comprising a pair of contact portions abutting the driver member and a pair of transmission portions on opposite sides of the inner shell between the contact portions; the outer shell being arranged so that the transmission portions act as bridging driver members between the said inner and outer shells, flexure of the outer shell being driven, on actuation of the transducer, by movement of the bridging driver members. The transducer may act as a push or pull actuator or sensor, may magnify displacement and may employ smart materials as driver members. Also cylindrical modules containing thin flextensional actuators may provide axial displacement in a downhole environment and may move a device axially along a downhole pipe or close a valve opening or inch along the pipe.

Transducer

A high pressure pump for use in the injection of liquid chemicals into subsea oil or gas wells, and intended to be positioned in the subsea environment adjacent to the wellhead, comprises a piezoelectric actuator () for reciprocating a plunger () which acts to compress and expand the effective volume of a pumping chamber () having a valved inlet () connected to a source of the liquid and a valved outlet () to lead the liquid to the well. The device has a minimum of moving parts and in particular avoids the need for any rotating parts and attendant high performance bearings and seals.

Subsea chemical injection system and pumps therefor

In order to check the authenticity of a banknote or other such document it is printed with two patches of magnetisable ink, and each patch is magnetised to present a multipole sequence of alternating polarity. If the document is folded to bring the two patches together and then rubbed to and fro in the direction of the pole sequences, they will be subject to alternating forces of attraction and repulsion which can be sensed through the fingertips and gives the impression of a physically rippled texture notwithstanding that the patches actually have a smooth surface. The presence or absence of this effect can therefore be used to distinguish between a genuine document bearing such magnetised patches and a counterfeit which may be visually identical but lacks the correct magnetisation. In a variant only one of the patches is printed on the document itself and the other is on a separate 'key' device which is rubbed over it to test for the presence of the correct magnetisation.

Documentation authentication

A stress or magnetic field sensor comprising a generally elongate magnetically soft amorphous or nanocrystalline electrically resistive element and biasing means for applying to the element a bias magnetic field of which the component directed along the length of the sensor has an amplitude variation pattern along the element. A periodically varying pattern has the effect of reducing the sensitivity of a stress sensor to external ambient fields (FIG.shows that with a sawtooth bias field the sensitive portions a of a sensor move to positions b in the presence of an ambient field, but their number remains the same). A ramped bias field enables the position of the sensitive region of the sensor to be controlled, for measuring local stress, or for mapping an external magnetic field. Control of the regions where the sensor is active may include selective conductive coating of portions of its length. Potential uses of the stress sensor include a pressure sensor, embedment in moving parts (using rf communication) such as vehicle tyres, aircraft wings or machine parts, and in structures such as bridges where stray magnetic fields are a problem.

Stress or magnetic field sensor with spatially varying bias

An integrating magnetic sensor is described which comprises a sensor element made from a filament of substantially amorphous material which exhibits giant magneto-impedance and means for applying a bias field to the said sensor element so that it operates in the high field section of the giant magneto-impedance response.

Elongate GMI integrating magnetic sensor

Growing community of inventors

Farnborough, United Kingdom

Jonathan Geoffrey Gore