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: The present application relates to a cold plasma device (13) for treating a surface (6) with cold plasma. The device (13) has a cold plasma generator (14) adapted to generate cold plasma that produces reactive species for treating the surface (6). The device (13) also includes a treatment head (5) that is positionable relative to the surface (6) such that the reactive species are imparted toward the surface (6) during treatment. The device (13) is also provided with an air flow generator (8) to generate an air flow over the surface (6) and a controller (9) configured to control operation of the air flow generator (8) to generate an air flow over the surface (6) after the treatment has been completed such that remaining by-products of the cold plasma are dissipated.

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: The invention provides an electroactive polymer actuator comprising a capacitance compensation means adapted to at least partially offset any changes in the capacitance across the member induced by its deformation. In this way, the electronic control of the device is rendered much simpler, since a varying capacitance across the actuator member does not have to be accounted for when driving the actuator to perform a particular deformation.

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: 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: 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 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: The proposed device comprises a plurality of electroactive material actuator units (20) arranged as a set. Control data for driving individual units is transferred over three shared power lines (Vop, Vop2, Vref). The electroactive material actuator (21) of each unit (20) is driven depending on control data received from the power lines via a demodulator (24), a controller (26), and a driver (28).

Abstract: The present disclosure relates to the fields of medical technology as well as fitness and activity trackers. To provide improved wearing comfort, in particular by reducing skin irritation, a wearable device (10) adapted to be worn by a user (100) is presented. The wearable device comprises a fixation element (12) for fixing the wearable device to the user, a lower side (15) for contacting a skin (101) of the user when worn; and a processing unit (20) adapted to determine a sweat level measure (32) indicative of an amount of sweat accumulated between the lower side (15) of the wearable device and the skin (101) of the user and indicative of an exposure to sweat over time; and to determine a moment in time for ventilating said lower side of the wearable device based on a said sweat level measure (32). The present disclosure further relates to a corresponding system and method.

Abstract: A sensor device comprising a passive matrix array of electroactive sensor elements arranged in rows and columns. In one example, each sensor element generates a binary sensor signal such that a total signal at each row and at each column enables any pattern of external inputs to be determined. This provides a first way to determine a pattern of sensor elements which are sensing an input using a passive matrix addressing scheme. In another example, each sensor element generates a sensor signal with a different frequency characteristic. This provides another way to enable any pattern of external inputs to be determined.

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 apparatus comprises a sensor for measuring a physiological parameter of a subject, wherein the physiological parameter sensor is adapted to be worn by the subject; an actuator comprising an electro-active polymer material, EAP, portion for adjusting the position of the physiological parameter sensor relative to the subject; a feedback sensor for measuring movement of the physiological parameter sensor and/or the subject; a controller configured to process the measurements of the feedback sensor and to adjust the position of the actuator based on information from the feedback sensor.

Abstract: An electroactive material actuator and sensor is actuated with an actuation signal having an activation period for charging the actuator and a de-activation period for discharging the actuator. A parallel resistance of the actuator is determined by sensing a steady state current during the activation period and a series capacitance of the actuator is determined based on a charge flow during charging of the actuator at the beginning of the activation period. A series resistance is obtained by controlling a current through the actuator with an oscillating profile so that a phase relationship of the actuator between current and voltage can be measured. An oscillating current sink is used to enable circuit component measurements, which implement sensing functionality.

Abstract: A field-driven electroactive polymer actuator is provided with a current sensor for sensing a current flowing to the actuator. A control circuit is used for driving the actuator which includes a voltage source. The driving of the actuator is controlled in dependence on the sensed current, thereby to provide a predetermined charge delivery for particular changes in actuation level of the actuator. This provides a combined voltage-based and current-based drive scheme for a voltage-driven EAP actuator, and it enables mechanical movements of the actuator to be more reliably repeated.

Abstract: The invention provides a field-driven electroactive material actuator that is driven by an actuation voltage. A driver is adapted to drive the actuation voltage from a first voltage level to a second voltage level, wherein the second voltage level is lower than the first, by way of a transition function, the transition function occurring over a transition time. The transition function includes a smoothing function. The transition time is at least 0.5 ms.

Abstract: A device comprises a plurality of electroactive material actuator units arranged as a linear set. Data for controlling the driving of the individual units is provided on a data line, and data line connections are made between each adjacent pair of electroactive material actuator units. The electroactive material actuator units are controlled in dependence on received data from the data line. This provides a reduced complexity of the wiring when multiple actuators need to be addressed and controlled in small application environments.