In some embodiments, the present invention is directed to an actuator which includes at least the following: a pre-stretched electro-active polymer film being pre-stretched in a single or biaxial planar directions; at least one first semi-stiff conductor attached to a first surface of the pre-stretched electro-active polymer film, wherein the first surface is parallel to the single or biaxial planar stretch directions; at least one second semi-stiff conductor attached to a second surface of the pre-stretched electro-active polymer film, wherein the second surface is opposite to the first surface; where the semi-stiff conductors are configured to: fix the pre-stretched electro-active polymer film in a pre-stretched state and allow the pre-stretched electro-active polymer film to expand; a pair of mechanical connectors coupled to each end of an active region of the pre-stretched electro-active polymer film.

Some embodiments relate to compositions for active compression devices and related methods. In some embodiments, a composition for an active compression device comprises an electro-active polymer film. In some embodiments, the electro-active polymer film comprises at least one polymer and at least one additive.

Provided is a piezoelectric substrate including: an elongate conductor; and an elongate first piezoelectric material helically wound in one direction around the conductor, in which the first piezoelectric material includes an optically active helical chiral polymer (A), the lengthwise direction of the first piezoelectric material and the principal orientation direction of the helical chiral polymer (A) included in the first piezoelectric material are substantially parallel to each other, and the first piezoelectric material has an orientation degree of F. in a range of from 0.5 to less than 1.0, determined from X-ray diffraction measurement by the following Formula (a):
orientation degree F.=(180°−α)/180°  (a) (in Formula (a), α represents a half width of a peak derived from orientation).

A vending machine interface includes a front panel, a product selection panel, and a piezoelectric element. The front panel bends in a normal direction when being pushed by a user. The product selection panel is disposed facing the front panel. A detection element is attached to the product selection panel and configured to detect bending of the front panel.

Provided is a piezoelectric laminate element that outputs a fixed output voltage even in response to a static load for which an output voltage could not be obtained using a conventional piezoelectric element. A piezoelectric laminate body in which a plurality of piezoelectric polymer film layers consisting of film such as polylactic acid film that exhibits piezoelectricity in the planar direction are laminated is used as a piezoelectric laminate element. The piezoelectric laminate body is given a cylindrical shape, rounded rectangle shape, or other partially curved shape. The output voltage follows the increase and decrease of the applied load, and if a fixed load is continuously applied, a fixed output voltage is continuously output, and a piezoelectric laminate element is obtained that outputs a fixed output voltage even if a load is static.

A voltage transformer including a beam or membrane made of a first polymer material having a resonance frequency in the range from 1 Hz to 1,000 Hz and including on the beam or membrane a stack successively including: a first electrode; a first piezoelectric layer made of a second polymer material; a second electrode; a second piezoelectric layer made of a third polymer material identical to the second polymer material or different from the second polymer material; and a third electrode.

In an embodiment a device includes a piezoelectric transducer element and a support connected mechanically to each other thereby forming an assembly, wherein the piezoelectric transducer element and the support are configured to be jointly deformed under an action of a first force, wherein the support includes a neutral fiber arranged inside the support, the neutral fiber configured to not undergo any change in length during a bending of the assembly, and wherein the piezoelectric transducer element includes a ferroelectric polymer layer or a layer having a composite material including a ceramic material and a piezoelectric polymer matrix.

Sensing an environment by confining a monitored live subject in an enclosure, detecting an effect on a coaxial piezoelectric cable resulting from the monitored live subject, wherein the coaxial piezoelectric cable is located at least proximate to the enclosure, and deriving information about a state of the monitored live subject based on the detected effect.

An ultrasonic sensor includes a substrate, a platen and an acoustic stack disposed between the substrate and the platen, including at least one piezoelectric layer. The ultrasonic transducer exhibits a signal-to-noise ratio of at least 4 over a frequency range of at least 9 to 16 MHz.

A piezoelectric sensor configured to detect a change of pressure from a living body in a predetermined location includes: a pair of electrodes spaced from one another and formed to spread as a sheet; a pressure-sensitive layer disposed between the pair of electrodes and configured to generate electric charge in response to the change of pressure; a pair of terminals connected to the pair of electrodes, respectively, and configured to output an electrical signal supplied from the pair of electrodes in response to the change of pressure of the living body. An edge of at least one of the pair of electrodes extending toward the pair of terminals is disposed to protrude outside the pressure-sensitive layer, and the electrical signal propagates through the edge and is outputted from the pair of terminals.