Described herein is a novel piezoelectric energy harvester based on a metamaterial structure capable of scavenging energy from multiple low-frequency ambient vibrations employing a mass-in-mass Phononic crystal structure and comprised of a piezoelectric snail structure, encapsulated in a cylindrical rubber matrix, and encased in a rigid cubic frame.

A piezoelectric coaxial sensor includes: a sensor portion including a center conductor having a linear shape, a polymer piezoelectric layer containing polyvinylidene fluoride and that covers an outer peripheral surface of the center conductor, and a first outer conductor that surrounds an outer peripheral surface of the polymer piezoelectric layer; and jacket layers that each include a film having a tape shape wound to surround an outer peripheral surface of the sensor portion. The film of at least one of the jacket layers exposed to the outside of the piezoelectric coaxial sensor among the other jacket layers is adhered to a member in contact with an adhesive layer by the adhesive layer. The adhesive layer includes a thermoplastic resin having a melting point of 120° C. or lower.

A piezoelectric coaxial sensor includes: a sensor portion including a center conductor having a linear shape, a polymer piezoelectric layer containing polyvinylidene fluoride and that covers an outer peripheral surface of the center conductor, and a first outer conductor that surrounds an outer peripheral surface of the polymer piezoelectric layer; and jacket layers that each include a film having a tape shape wound to surround an outer peripheral surface of the sensor portion. The film of at least one of the jacket layers exposed to the outside of the piezoelectric coaxial sensor among the other jacket layers is adhered to a member in contact with an adhesive layer by the adhesive layer. The adhesive layer includes a thermoplastic resin having a melting point of 120° C. or lower.

Provided is a vibration presentation device that includes a plurality of vibration actuators that vibrate when voltage is applied, and a control unit that controls vibration to be generated in the plurality of vibration actuators. The vibration actuators include a flexible, lightweight, and thin material, and are in surface contact with the portion to be presented with vibration. The control unit then generates a vibration signal for each of the plurality of vibration actuators, and controls the vibration for the plurality of vibration actuators independently of one another.

The present invention relates to a pressure signal detection circuit and a pressure signal detection method in which a pyroelectric signal from a piezoelectric film is suppressed. More specifically, the pressure signal detection circuit receives input of an input signal from a piezoelectric film, differentiates the input signal for signal component analysis of the input signal, outputs the signal analysis value of the input signal based on the differential value, removes offset of the input signal by using the signal component analysis value, integrates the input signal, and outputs a pressure input signal value from which a heat input signal value is removed.

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.

A hybrid RF-acoustic relay is provided where some but not all of the incident RF power is rectified to power the relay and, optionally, to provide power for further link features. The remaining fraction of the incident RF power is used to directly drive an acoustic transceiver array in communication with one or more acoustically powered nodes. In this manner, power, control and communication can be efficiently provided to acoustically powered nodes even in situations where an RF link or an acoustic link would perform poorly.

Embodiments of the present disclosure relate to a display substrate, a method for manufacturing the same, and a display device. The display substrate includes a substrate, a pixel definition layer for defining pixels on the substrate, the pixel definition layer including a plurality of inter-pixel portions located between adjacent pixels, and a fingerprint recognition sensor located in the inter-pixel portions.

A funnel-shaped underwater energy harvesting equipment includes a piezoelectric element configured to be installed at a seabed and to be moved by a fluid in order to convert vibration energy into electricity. The funnel-shaped underwater energy harvesting equipment further includes a fluid collector coupled to the piezoelectric element and configured to increase velocity of the fluid flowing toward the piezoelectric element. The harvesting equipment exhibits improved energy conversion efficiency, while simplifying the shape of the harvesting equipment.

A vibration structure that includes a film having a first electrode on a first main surface thereof, the first electrode defining a first connection region on the first main surface where the first electrode is not present, and the film is constructed to be deformed in a plane direction when a voltage is applied thereto; a frame-shaped member; a vibration portion surrounded by the frame-shaped member; a first connection member that connects the first main surface of the film to the frame-shaped member at the first connection region; a second connection member that connects the film to the vibration portion; and an extended electrode that is connected to the first electrode.