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.

An actuator includes a stack including: an elastomer layer; and an elastic electrode disposed on each surface of the elastomer layer, in which the stack is subjected to a pre-strain of 50% or more at least in one direction. The stack may have a round tubular shape with the elastic electrodes disposed on opposite surfaces of the elastomer layer in a radial direction of the stack.

An actuator includes a laminate including an elastomer layer and an electrode, in which the laminate has a spiral or concentric shape, pre-distortion is applied to at least one member out of the elastomer layer and the electrode, and area distortion of the at least one member is 10% or larger.

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 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.

The present application relates to stacked piezoelectric composites comprising piezoelectric structures. Suitably, the composites are useful as tissue-stimulating implants, including spinal fusion implants. The present application also relates to methods of making stacked piezoelectric composites.

A piezoelectric transformer is disclosed In an embodiment a piezoelectric transformer includes a cylindrical base body with an input region and an output region, wherein a cylinder axis of the base body extends in a longitudinal direction, wherein the input region is configured to convert an AC voltage into a mechanical vibration, wherein the output region is configured to convert a mechanical vibration into an electrical voltage, wherein the output region includes a single piezoelectric layer polarized in the longitudinal direction, wherein, in the input region, a first piezoelectric layer, on which a first internal electrode is arranged, and a second piezoelectric layer, on which a second internal electrode is arranged, are wound onto one another, and wherein the first piezoelectric layer and the second piezoelectric layer are polarized in a radial direction which is perpendicular to the longitudinal direction.

A helical dielectric elastomer actuator (HDEA) can include a first dielectric region comprising an elastomer defining a helix. In an example, a dielectric material can be deposited and a compliant conductive material can be deposited, such as using an additive manufacturing approach, to provide an HDEA. In an example where the HDEA has multiple mechanical degrees of freedom, at least two compliant conductive regions can be located on a first surface of the first dielectric region and at least one compliant conductive region can be located on an opposite second surface of the first dielectric region. For such an example, the at least two compliant conductive regions can be arranged to be energized with respect to the at least one compliant conductive region in a manner providing at least two mechanical degrees of freedom for operation of the HDEA.

An actuator includes a laminate including an elastomer layer and an electrode, in which the laminate has a spiral or concentric shape, pre-distortion is applied to at least one member out of the elastomer layer and the electrode, and area distortion of the at least one member is 10% or larger.

The present application relates to stacked piezoelectric composites comprising piezoelectric structures. Suitably, the composites are useful as tissue-stimulating implants, including spinal fusion implants. The present application also relates to methods of making stacked piezoelectric composites.