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.

Abstract: An actuator device has an electroactive polymer actuator (35) and an integrated piezoelectric transformer (30) whose primary side (32) and secondary side (34) are formed from different electroactive polymer materials. At least the secondary side (34) of the transformer shares a piezoelectric electroactive polymer layer (36) with the electroactive polymer actuator, so that lower external voltages can be applied to the device.

Abstract: A wirelessly controllable device comprises responsive material actuator elements, each driven by a respective receiver circuit having an inductive coil for receiving electrical energy inductively. Each circuit has a different respective resonance frequency. This allows for wireless selective activation of the actuators by applying a magnetic field having frequency components matching the circuits of only those actuator elements which are desired to be activated. A system is further provided, comprising a wirelessly controllable device and a control unit, the control unit having a transmitting inductive coil arrangement for supplying electrical energy to circuits of the wireless device by inductive coupling. A frequency spectrum of the applied field is configured to control which of the actuator elements are activated.

Abstract: There is provided a wearable device operable to determine an orientation of the wearable device, when placed on a body. The wearable device comprises a plurality of electrode pairs located at different positions. At least two of the plurality of electrode pairs are configured to receive a signal transmitted from a reference device using the body as a transmission medium. The wearable device also comprises a processor configured to determine a property associated with the signal received at the at least two electrode pairs, compare the determined property to a corresponding reference property and determine, from the comparison, whether the wearable device is in the predetermined orientation on the body. The determined property is indicative of an orientation of the wearable device with respect to the reference device and the corresponding reference property is indicative of a predetermined orientation for the wearable device on the body.

Abstract: An autostereoscopic display device uses an electroluminescent display. A set of pixels is provided beneath view forming elements (such as lenses), with a plurality of pixels across the view forming element width direction. The pixels are arranged with at least two different angular orientations with respect to the substrate. The out-coupling performance is improved by arranging for the light emission direction to be substantially perpendicular to the desired emitting surface of the view forming elements.

Abstract: There is provided a method of manufacturing a cutting element for use in a hair cutting device, the cutting element comprising an optical waveguide, the method comprising providing a preform for an optical waveguide, the preform comprising a core and an outer layer, wherein the outer layer is arranged around the core along the length of the core; forming a shaped preform by removing a portion of the outer layer along the length of the core to expose part of the core, wherein a remaining portion of the outer layer is a support structure for the core; heating the shaped preform; and pulling the shaped preform in the direction of the axis of the core to reduce the cross-section of the shaped preform and form the optical waveguide.

Abstract: An oral cleaning device comprises a body which carries a set of projections. An actuator device is associated with one or more of the projections in the form of an electroactive polymer structure for adjusting a position of the associated one or more projections. This enables dynamic control of the cleaning function.

Abstract: There is provided a method (500) of treating an optical waveguide. The method comprises applying (502) the volume of ferrofluid to the optical waveguide, and applying (504) a magnetic field to the volume of ferrofluid to move the volume of ferrofluid at least partially along a length of the optical waveguide. A personal care device and a system are also disclosed.

Abstract: An actuator member has a body formed of a composite material of electroactive material (EAM) particles and a compliant matrix material. The composite material of the body is materially structured such that it incorporates one or more continuous material paths extending between a first and second major surface of the actuator body, each path including at least one EAM particle, and wherein all material of the path has an electrical resistivity equal to or less than that of the EAM particle(s).

Abstract: The invention provides an ultrasound transducer device comprising an electroactive polymer (EAP) element coupled atop a capacitive micromachined ultrasonic transducer (CMUT) element, wherein the two elements are controlled to vibrate concurrently at a common frequency by application to each of a drive signal of the same AC frequency.

Abstract: An active matrix array of electroactive polymer actuators is provided, each electroactive polymer actuator having a switching arrangement. The switching arrangement comprises a first circuit (90) connected to a first terminal of the electroactive polymer actuator, for selectively driving the first terminal of the electroactive polymer actuator to ground or connecting it to an open circuit. A second circuit (92) is connected to a second terminal of the electroactive polymer actuator, for selectively driving the second terminal of the electroactive polymer actuator to ground or connecting it to an open circuit. Furthermore, a pull-up component (50) is permanently connected between a drive voltage and the first terminal of the electroactive polymer generator. By controlling both terminals of the electroactive polymer actuator, it is possible to reduce static power consumption, at least when no voltage is to be stored across the electroactive polymer actuator.

Abstract: A system comprises a power generator for generating electrical power and a switched capacitor converter for down-converting the output voltage of the power generator. The switched capacitor converter comprises a bank of capacitors and a switch arrangement. A controller is used for controlling the switches, based on a feedback signal from the power generator. This provides automatic control of the switched capacitor converter, thereby simplifying the overall control circuitry and improving efficiency.

Abstract: The invention provides a device for generating electrical currents of a particular desired waveform through the combining of a plurality of different frequency output currents generated by plurality of power generating arrangements. The power generating arrangements each comprise at least first and second sets of generating elements, configured to hold a relative charge and to be moveable with respect to one another in order to generate an electrical output current of a particular frequency.

Abstract: A biological cell preservation or culturing arrangement (20) comprises a chamber defining a fluid retaining space (30) for retaining in use a body of fluid (34) and a deformable membrane (36) in communication with the fluid retaining space, and being manipulable by an electroactive polymer actuator arrangement (38) to undergo a defined topology change to induce in the fluid a pattern of fluid flow by which fluid is exchanged between a sub-region (46) immediately proximal the deformable membrane and a sub-region (48) removed from the deformable membrane.

Abstract: An actuator structure includes an electroactive material-based active layer structure which exhibits an intrinsic variation in actuation displacement as a function of temperature. A passive compensator is provided to modify a current or voltage of an electrical stimulation applied to the active layer structure as a function of temperature such as to compensate for the thermally-induced variation in actuation displacement. The passive compensator comprises a multi-layer temperature-dependent capacitor structure, and is formed by layers of a passive carrier layer structure provided coupled to the active layer structure.

Abstract: An autostereoscopic display device uses an electroluminescent display. A set of pixels is provided beneath view forming elements (such as lenses), with a plurality of pixels across the view forming element width direction. The pixels are arranged with at least two different angular orientations with respect to the substrate. The out-coupling performance is improved by arranging for the light emission direction to be substantially perpendicular to the desired emitting surface of the view forming elements.

Abstract: An actuator device comprises an active matrix array of rows and columns of electroactive polymer actuators, each electroactive polymer actuator having a switching circuit. The switching circuit has a drive transistor and a capacitor arrangement. The capacitor arrangement is charged to a voltage derived from a drive voltage for the electroactive polymer actuator combined with a voltage derived from the drive transistor threshold voltage. During this programming of the capacitor arrangement, the EAP actuator is isolated from any current flowing. The switching circuit enables compensation for age-related changes in the threshold voltage. Thus, a low performance (i.e. with poor threshold voltage stability) transistor may be used, with measurement of the threshold voltage of the current-providing TFT once per frame time (or once per multiple frame times) to compensate for the aging effect.

Abstract: An ultrasound interface element (10) is for establishing interface with an incident tissue surface (32) for the purpose of transfer of ultrasound waves. An ultrasound-transmissive active layer (14) is provided comprising one or more responsive material elements (16) deformable in response to an electromagnetic stimulus. The one or more elements are controlled to deform in a manner such as to progressively establish with the tissue surface (32) an outwardly expanding interface, starting from an initial point or line of contact and spreading outwards to a wider area.

Abstract: An actuator device is provided having a controllable stiffness profile, wherein an actuator member (12) comprises an electroactive polymer material (16) having light absorbing filler elements (20) embedded therein. The filler elements are adapted to absorb and convert incident light (26) to heat energy to therefore heat surrounding sections of the electroactive material. By selectively controlling an intensity level or spectral composition of a light source (24) directed at the actuator member, a specific degree and spread of heating can be achieved across the member and, as a result, a specific desired stiffness or flexibility profile can be realised across the actuator member.

Abstract: A nozzle (12) for an oral irrigator device (10) having a guidance tip (34) with an orifice at one end, and a dynamic nozzle actuator (64) positioned within said guidance tip. The orifice (36) is configured to expel a fluid as one of a jet, a spray, or any combination thereof. The dynamic nozzle actuator (64) comprises at least one responsive material adapted for being energized and configured to implement at least one dynamic actuation of an effective channel (62) for dynamically influencing at least one of (i) a direction of fluid expelled from the orifice (36), (ii) an angle of fluid expelled from the orifice (36), (iii) a cross-sectional width of fluid expelled from the orifice (36), and (iv) any combination thereof.