Abstract: A system and method that adapts how an audio output is generated based on a response of a subject's sleep parameters to the audio output. In particular, one or more rules used to generate the audio output are modified in response to how values of sleep parameters (i.e. parameters responsive to a sleep state of the subject) change in response to the audio output. The audio output can be iteratively modified to assess the impact of different audio outputs.

Abstract: The invention provides a device (and method) for masking noise in which a calibration is carried out to determine the sensitivity of a user to a calibration sound. During use of the device, the signal characteristics of the masking sound are adjusted based on the detected noise, the response of the user to the detected noise and also the response of the user to the calibration sound. As a result, a masking sound is generated that is optimally adapted to mask unwanted noise, in particular in a way which avoids the masking noise itself becoming a disturbance to the particular user.

Abstract: An actuator or sensor device comprises an electroactive polymer (EAP) arrangement which extends between fixed opposite ends. The electroactive polymer arrangement comprises a passive carrier layer and an active electroactive polymer layer, wherein at or adjacent the ends, the passive carrier layer and the active EAP layer are mounted with one over the other in a first order, and at a middle area between the ends, the carrier layer and the active EAP layer are mounted in an opposite order. This enables internal stresses and moments within the electroactive polymer arrangement to be used more effectively to contribute to displacement or actuation force.

Abstract: An actuator device has an electroactive polymer actuator and an integrated piezoelectric transformer. At least a secondary side of the integrated piezoelectric transformer shares a piezoelectric electroactive polymer layer with the electroactive polymer actuator, so that lower external voltages can be applied to the actuator device. A diode is connected between the secondary side of the integrated piezoelectric transformer and the electroactive polymer actuator.

Abstract: An electroactive material actuator is clamped along one edge (12) and has a pre-bend about a first axis (21) which is parallel to said edge and/or about a second axis which is perpendicular to said edge. The actuator expands with expansion coefficients along the first and second axes which differ by less than 20%. This combination of isotropic (or near isotropic) expansion with a pre-bend across at least one of main axes of the device (i.e. the axes which form the general plane of the actuator) gives rise to various additional operating characteristics.

Abstract: A physiological sensor apparatus offers auto-adjustment of a physiological sensing surface relative to a human tissue receiving surface. The apparatus includes an electroactive polymer (EAP) structure, operable to perform actuation and pressure sensing simultaneously, via application of superposed actuation and AC sensing signals. Actuation enables controlled adjustment of the positioning of a sensing surface against the tissue receiving surface. Sensing provides a simultaneous real-time measure or indication of the magnitude of a returning force applied to the sensing surface by the receiving surface. This returning force provides feedback on the state of positioning of the sensing surface. A controller is adapted to adjust the actuation signal in dependence upon the sensing data, to thereby adjust the positioning of the sensing surface in real-time.

Abstract: A friction control device (44) is adapted to induce a lateral strain (or stretching) within a human tissue surface to which the device is applied, in order thereby to reduce the static friction between the device and the human tissue surface. The strain is induced by means of an actuator arrangement adapted to effect a relative separation of a plurality of contact surface regions (40) of the device, such that when said regions are pressed onto the receiving surface, the relative separation induces a strain in at least the region of the receiving surface falling between the locations of the applied regions. The extent of separation matches or exceeds the minimum extent necessary to overcome static friction.

Abstract: An invasive medical device (10) is disclosed comprising a device portion (15) for inserting into a patient, said device portion including a functional module (20); an electrically conductive path (40) extending through the invasive medical device and connecting to the functional module; and a deformable switch (30) within the device portion arranged to alter the electrical impedance of said conductive path as a function of a degree of deformation of the switch, said deformation being caused by a blood parameter of the patient's blood that varies during the cardiac cycle of said patient.

Abstract: A device for treating skin includes a skin treatment member, a skin contacting surface, a mounting member for mounting the skin treatment member and the skin contacting surface, and a friction controlling device to control friction between the skin contacting surface and skin to be treated, in at least one controlled friction area of the skin contacting surface when the skin contacting surface is moved over the skin. The friction controlling device introduces a slip motion of the controlled friction area relative to the mounting member in a direction corresponding to a local direction of extension of the skin contacting surface. The device also includes a sensor for detecting a first parameter related to an amount of friction between the skin contacting surface and the skin during use, and the friction controlling device controls a second parameter of the slip motion in dependence on a value of the first parameter.

Abstract: The invention provides a surface analysis device for application to a receiving surface to enable analysis of at least one measure of an elasticity of said surface across multiple different linear stretches or sections of the surface. The device includes a two-dimensional arrangement of actuators and sensors, comprising at least one actuating element, at least one sensing element, and at least one further sensing or actuating element. Selected sets of two or more of these elements are activated together by a controller, each set including at least one actuator and one sensor, to thereby obtain a measure of elasticity between each actuator and sensor pair in the set. Elasticity measures are obtained based on stimulating a deformation in the receiving surface at the actuator site, and measuring a resultant pressure and/or force exerted by the receiving surface at a further displaced point. Sensors may monitor a change in the exerted pressure and/or force for example.

Abstract: An implantable blood flow control system has an open passageway defined inside a radially inner wall, behind which is a closed passageway. The radially inner wall includes electroactive polymer actuator members for providing a variable flow restriction. The flow restriction has an undulating shape so that the volume of the closed passageway may remain constant during actuation of the electroactive polymer actuator members. In this way, the chamber behind the actuator members does not impede free movement of the actuator members. The undulating pattern presents no sharp edges, where blood coagulation could otherwise occur.

Abstract: The invention provides an electroactive material (preferably electroactive polymer) sensor system, comprising an electroactive material sensor (22) and a control system (28) for performing measurements relating to the impedance of the electroactive material sensor at at least first and second different frequencies. From these measurements a temperature at the sensor and an external pressure or force applied to the sensor can be determined. The sensor can thus be used as a pressure sensor and as a temperature sensor. When used in combination with actuation, an electroactive material actuator with integrated temperature sensing functionality is able to measure the temperature at the exact actuator position, which is always closer than an external thermocouple.

Abstract: An actuator device comprises an electroactive or photoactive polymer arrangement having an effective length over which expansion or contraction is induced by actuation. The effective length is greater than the maximum linear physical dimension of the space occupied by the polymer arrangement. In this way, a compact design is provided which can support a large actuation displacement.

Abstract: A monitoring system comprises an intra-vascular support device and a sensor mounted to the support device and projecting into the vessel. The sensor generates a signal which is dependent on the level of deformation of a free end. The sensor signal is interpreted to enable detection of changes in the length of a deformable part of the sensor thereby to determine a level of bio-layer formation and also determine a level of flow. The sensor remains able to detect flow even when a bio-layer is formed and it can also detect the presence (and thickness) of the bio-layer, because part of the sensor becomes rigid when constrained by the bio-layer.

Abstract: An actuator device comprises an EAP structure which deforms in response to a drive signal applied to the device, a device output being derived from movement of the EAP structure. A delay arrangement is used such that the mechanical output from the device is not generated for a first range or type of applied drive signals, and said device output is generated for a second range or type of applied drive signals. This device is for example particularly suitable for use in a passive matrix system.

Abstract: A monitoring system includes an implantable intra-vascular support device for positioning against a vessel wall and an implantable sensor-actuator mounted to the support device. The sensor-actuator is drivable between a non-deployed position in which it is against the support device and a deployed position in which it is displaced away from the support device. Sensor signals are generated when in the deployed position. This system is able to monitor flow away from the edge of a vessel by deploying the sensor-actuator towards the center of the vessel. When flow monitoring does not need to take place, it can be non-deployed so that it does not present an occlusion to the flow.

Abstract: The invention provides a health device for automatically administering skin pressure-based therapies to a user. The device comprises one or more actuator members, each comprising a smart shape-changing material of a class which is disposed to change shape in response to a change in temperature or to the application of an electrical stimulus. The actuator members are controlled by a controller to apply pressure to one or more points on a user's skin.

Abstract: A system for determining a pulse wave velocity comprises a body lumen insertable device with an actuator for providing a pulse in the vicinity of a vessel wall and a sensor for sensing arrival of the pulse. A pulse wave velocity is obtained from the time difference between actuation of the actuator and sensing of the pulse. This system is used to create an artificial pulse which is transmitted along a vessel by a known distance before detection by a sensor.

Abstract: An actuator device has a temperature sensing means and a controller adapted to apply a high frequency AC signal to stimulate internal self-heating to thereby maintain a temperature of an actuator member of the device at a certain fixed temperature, this temperature being elevated with respect to an initial temperature of the actuator member. This ensures that thermal drift may be mitigated or eliminated by compensating for any changes in environmental temperature through raising or lowering the level of the heating signal.

Abstract: A field driven electroactive polymer actuator which is actuated using an actuation drive having a profiled portion having a start voltage and an end voltage and a duration of at least 25 ms followed by a steady state drive portion based on a steady state voltage. The profiled portion comprises a voltage curve or a set of voltage points which define a first voltage slope at the beginning of the profiled portion which is steeper than a linear ramp between the start voltage and the end voltage, and a second voltage slope at the end of the profiled portion which is shallower than a linear ramp between the start voltage and the end voltage.