An energy harvester includes a pendular unit subjected with a piezoelectric beam coupled to an inertial mass. On the clamped side of the beam, a beam frame includes two pressing elements between which the beam is taken in sandwich, each including i) an intermediate part, an internal face of which presses on a corresponding face of the beam, and ii) a pressure plate, an internal face of which presses on an external face of the intermediate part, a printed circuit board being interposed between them. The intermediate parts and the pressure plates are passed through by at least one common transverse bore receiving a locking pin. The intermediate parts, the pressure plates and the pin are each massive metal parts ensuring a direct electrical and mechanical contact with the electrodes of the beam and with the printed circuit boards.

A piezoelectric microelectromechanical systems microphone can be mounted on a printed circuit board. The microphone can include a substrate with an opening between a bottom end of the substrate and a top end of the substrate. The microphone can include a single piezoelectric film layer disposed over the top end of the substrate and defining a diaphragm structure, the single piezoelectric film layer being substantially flat with substantially zero residual stress and formed from a piezoelectric wafer. The microphone can include one or more electrodes disposed over the diaphragm structure. The diaphragm structure is configured to deflect when subjected to sound pressure via the opening in the substrate.

A four-sided-synchronous-swing dual-mode broadband power generation device, comprising a fixing frame, a piezoelectric beam swing mechanism, and electromagnetic induction power generators (7). Four groups of straight piezoelectric beams (6) and L-shaped piezoelectric beams (5) are installed in a small space, therefore, a limited working space can be fully utilized, the working area can be reduced, and the requirements for development of a microelectromechanical system can be satisfied. Each L-shaped piezoelectric beam (5) comprises a horizontal beam and a vertical beam, so that vibration in two directions can be implemented, therefore, the dynamic behavior of piezoelectric cantilevers is enriched, and the power generation efficiency of the system is improved. The straight piezoelectric beams (6) and L-shaped piezoelectric beams (5) have different lengths, so that energy of different swing frequencies can be effectively harvested, and the effective working frequency bandwidth can be broadened. The adjacent straight piezoelectric beams (6), L-shaped piezoelectric beams (5), and electromagnetic induction power generators (7) constitute four groups of dual-mode piezoelectric electromagnetic composite power generation structures, effectively improving power generation. The four-sided-synchronous-swing dual-mode broadband power generation device can harvest energy inputted in the form of rotation from environment and currently can be applied to wind power generation, hydroelectric power generation, bicycle self-power supply, and other fields.

An etching method for forming a vertical structure is provided. The etching method may include: positioning a mask on a substrate, wherein the mask includes an opening pattern and a compensation pattern, and the compensation pattern is disposed at a corner of two adjacent sides of the opening pattern and includes a concave compensation pattern that is indented from one of the two adjacent sides; and forming the vertical structure on the substrate through the opening pattern of the mask by a dry etching process.

An energy producing device includes a piezoelectric layer having a first side and second side opposite of the first side, a first electrical contact arranged on the first side of the piezoelectric layer, a second electrical contact arranged on the second side of the piezoelectric layer, and a counter-layer arranged on the second electrical contact. The piezoelectric layer, first and second electrical contacts, and counter-layer form a beam having a neutral axis outside of the piezoelectric layer.

A vibrational lens is disclosed. The vibrational lens comprises at least two focusing plates each having a proximal and distal end. The separation between the distal ends of the at least two focusing plates is less than the separation between the proximal ends of the at least two focusing plates. The vibrational lens transmits, converges and focuses vibrational energy from a source to an energy conversion means such as piezoelectric crystals. The vibrational lens may also comprise a bimetallic structure to convert thermal fluctuations into mechanical displacement. The vibrational lens is suitable for use in a vibrational and or thermal energy harvesting system. Advantageously, the vibrational lens improves the energy efficiency of, for example, an internal combustion engine whilst mitigating the need for vibrational damping mechanisms and or thermal insulation.

Described is an energy harvesting system comprising a transducer that generates an electric signal from ambient energy, and a processor adapted to process the electric signal to determine and output a characteristic of a source of the ambient energy. The characteristic may be a spoken word classification.

Systems and methods are provided that integrate control electronics with a wireless on-board module so that a conformal ultrasound device is a fully functional and self-contained system. Such systems employ integrated control electronics, deep tissue monitoring, wireless communications, and smart machine learning algorithms to analyze data. In particular, a stretchable ultrasonic patch is provided that performs the noted functions. The decoded motion signals may have implications on blood pressure estimation, chronic obstructive pulmonary disease (COPD) diagnosis, heart function evaluation, and many other medical monitoring aspects.

Energy harvesters (EH) which can effectively harvest wasted vibrational/kinematic energy and convert it into electrical energy for battery-free sensor operation are described herein. The energy harvesters can be integrated with a power management circuit and a wireless sensor for monitoring wind turbine blades. The target application of the energy harvesters includes powering the wireless sensors used for wind turbine blade structural monitoring.

A sensor device that senses proper acceleration. The sensor device includes a substrate, a spacer layer supported over a first surface of the substrate, at least a first tapered cantilever beam element having a base and a tip, the base attached to the spacer layer, and which is supported over and spaced from the substrate by the spacer layer. The at least first tapered cantilever beam element tapers in width from the base portion to the tip portion. The at least first cantilever beam element further including at least a first layer comprised of a piezoelectric material, a pair of electrically conductive layers disposed on opposing surfaces of the first layer, and a mass supported at the tip portion of the at least first tapered cantilever beam element.