A sensor unit capable of protecting a piezoelectric element and detecting vibration and sound is provided. The sensor unit comprises a sheet-like piezoelectric element having a porous layer, and a sound propagation sheet covering at least one face of the piezoelectric element and permitting transmission of sound from a first face toward a second face of the sound propagation sheet. A difference in acoustic pressure level between the sound incident on the sound propagation sheet and the transmitted sound is preferably no greater than 10 dB. A surface density of the sound propagation sheet is preferably from 0.03 g/m.sup.2 to 100 g/m.sup.2. The sound propagation sheet is preferably flexible and preferably has voids. The sensor unit preferably further comprises a sound insulation sheet covering another face of the piezoelectric element and substantially preventing transmission of sound from a second face toward a first face of the sound insulation sheet.

The present invention relates to a piezoelectric sensor using a piezoelectric polyvinylidene fluoride (PVDF) film. As an embodiment, there is proposed a piezoelectric sensor including: a PVDF film; an electrode layer which is formed on the top surface of the PVDF film; a substrate which is provided with a first electrode electrically connected to the electrode layer and a second electrode disposed at a location spaced apart from the first electrode; a non-conductive layer which covers the electrode layer; a first shield film which is electrically connected to the second electrode while being attached to the non-conductive layer; and a second shield film which is attached to the top surface of the PVDF film, and is connected to the first shield film while surrounding a stack of the PVDF film to the non-conductive layer.

A dielectric elastomer power generation system of the invention includes: a power generation unit including a dielectric elastomer power generation element having a dielectric elastomer layer flanked by two electrode layers; a step-down unit including capacitors; a power storage unit for input of an output power from the step-down unit; and a control unit that controls the connection between the step-down unit and the power generation unit or power storage unit. The step-down unit includes first diodes and second diodes, where the first diodes form a circuit that connects the capacitors in series when the power generation unit is connected to the step-down unit, and the second diodes form a circuit that connects the capacitors in parallel when the step-down unit is connected to the power storage unit. This configuration serves to store the generated power more efficiently in the power storage unit, e.g., a secondary battery.

The present invention provides a composition for forming a polyvinylidene fluoride film, which contains: a polyvinylidene fluoride; at least one surfactant that is selected from among sulfuric acid-based surfactants, sulfonic acid-based surfactants and quaternary ammonium salt type surfactants; and a solvent.

A material that includes a polymer foam and at least one polar dopant molecule included in the polymer foam, wherein the material is a piezoelectric.

The present invention discloses a flexible sensor detection system for medical care and health, including: an information collection module, which uses a wearable device as a carrier, where flexible sensors are respectively arranged on the wearable device; an information transmission module, configured to wirelessly transmit collected information to an information processing and feedback module; and the information processing and feedback module, configured to perform grading treatment on received data information and feed back a health condition corresponding to the data information to the information transmission module, where the information transmission module compares feedback health condition data with a preset health threshold to determine whether to give an alarm. A heart rate ECG band, a breathing band, a shell temperature band, a blood flow rate band, a blood glucose band, a blood oxygen band, and a deep temperature band of the present invention are provided with the built-in flexible sensors.

An antibacterial yarn that includes a core yarn including a functional polymer that generates a charge by external energy and a first sheath yarn higher in hygroscopicity than the core yarn, the first sheath yarn covering at least a part of a periphery of the core yarn across an axial direction of the core yarn.

The invention involves providing a reset signal before and or after one or more actuation signals to an electroactive polymer structure of an actuator. The reset signal can cause relaxation of defects such as e.g. trapped charge, dipoles and/or others in the EAP or EAP structure so that upon a subsequent activation using a drive signal, the initial actuation state is defined to be more constant than without use of the reset signal. Hence the actuation 5 output of a device employing the invention is more reproducible. The invention is applicable to actuator devices that have an electroactive polymer structure including an EAP material, where the structure is capable of providing a mechanical actuation upon subjection of at least part of the EAP material to an electrical drive signal.

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.

Aspects of the present disclosure describe systems, methods, and structures that scavenge mechanical energy to provide electrical energy to a wearable, where the mechanical energy is scavenged by a bending-strain-based transducer that includes a non-resonant energy harvester. By employing a non-resonant energy harvester that operates in bending mode, more electrical energy can be generated that possible with prior-art energy harvesters. In some embodiments the bending-strain-based transducer also includes a sensor and/or a haptic device. Some transducers in accordance with the present disclosure comprise a piezoelectric layer comprising a low-K piezoelectric material, such as aluminum nitride, which enables generation of higher voltage and power/energy output and/or a thinner transducer. As a result, transducers in accordance with the present disclosure can be included in wearables for which large transducer thickness would be problematic, such as sole members (e.g., shoe insoles, midsoles or outsoles), garments, bras, handbags, backpacks, and the like.