Abstract: The harvester comprises a pendular unit comprising a beam that is elastically deformable in bending, a mount clamping a proximal end of the beam, and an inertial mass mounted at a free, distal end of the beam. The beam converts into an oscillating electric signal a mechanical energy produced by pendular unit oscillations. The beam comprises a flexible structure including a central core, a piezoelectric layer on at least one face of the central core, and at least one surface electrode on an external face of the piezoelectric layer. The central core of the flexible structure is made of a semiconductor material adapted to form an integrated circuit substrate. The substrate made of a semiconductor material of the central core includes monolithic integrated structures, and the arrangement, over the extend of the central core substrate, of said integrated structures forms in the longitudinal direction a plurality of successive areas having different bending stiffness coefficients from an area to another.

Abstract: A light-emitting module structure comprises a support substrate and a micro-module disposed on or in the support substrate that extends over only a portion of the support substrate. The micro-module comprises a rigid module substrate, an inorganic light-emitting diode, a power source, and a control circuit. The inorganic light-emitting diode, the power source, and the control circuit are disposed on or in the module substrate and the control circuit receives power from the power source to control the inorganic light-emitting diode to emit light. A light conductor is disposed on or in the support substrate and in alignment with the micro-module so that the inorganic light-emitting diode is disposed to emit light into the light conductor and the light conductor conducts the light beyond the micro-module to emit the light from the light conductor.

Abstract: An operating device for a human powered vehicle comprises a base member, a first operating member, a piston, and an electric generator. The base member includes a cylinder bore. The first operating member is configured to be movably coupled to the base member between a first rest position and a first operated position. The piston is configured to be movably provided in the cylinder bore and to be pulled in response to a movement of the first operating member from the first rest position toward the first operated position. The electric generator is configured to generate electric power in accordance with a physical change applied to the operating device.

Abstract: A watch includes a case, a display for displaying a plurality of symbols, a processor in signal communication with the display, and configured for controlling the display in a manner such that they will display a screen where at least one first symbol is selected among a plurality of available symbols, a rotary crown associated with the case, and a motion detector configured for detecting at least the rotary motion of the crown, wherein the motion detector is in signal communication with the processor, and wherein the processor is also configured for controlling the display in a manner such that, when the crown is turned, at least one other symbol, different from the first symbol, will be selected among a plurality of available symbols.

Abstract: An energy harvester includes an electrode part including a plurality of partition walls spaced apart from one another in a horizontal direction, and spaces defined between the plurality of partition walls, and a cantilever part including a cantilever member having at least a partial region provided in the space defined in the electrode part, the cantilever member includes a plurality of cantilever members, each of the plurality of cantilever members having a first end and a second end, wherein the first end is positioned in the space defined in the electrode part, and wherein the second end is fixedly coupled to a housing, and in which a natural frequency of at least one of the plurality of cantilever members is different from a natural frequency of each of the remaining cantilever members.

Abstract: A kinetic energy harvesting device implementing a half-wave mechanical motion rectification (HMMR) mechanism is described. The energy harvesting device may include an energy harvesting railroad tie, where the tie includes a tie housing configured to be coupled to at least one rail. The tie housing includes at least one spring and at least one energy harvester. The at least one energy harvester includes a generator having an output shaft, a gearhead, a ball screw or other motion transmission, and a one-way clutch. Under a force of a passing wheel on the at least one rail, the at least one energy harvester is compressed, which causes a rotation of the ball screw or other motion transmission, a rotation of the output shaft, and a transmission of torque to a shaft of the gearhead, driving the generator in a unidirectional rotation to generate electrical power via the one-way clutch.

Abstract: Piezoelectric vibrational energy harvesters (PVEHs) include a Macro Fiber Composite (MFC)) piezoelectric transducer coupled to a cantilever to harvest vibrational energy. One or more Ionic Polymer Metal Composite (IPMC) strips are situated to provide device tuning over a wide frequency range by applying variable contact force to the cantilever. Power consumption for tuning is sufficiently low that the tuning actuator (IPMCs) can be powered using harvested energy.

Abstract: Provided is a piezoelectric valve in which the valve is opened/closed utilizing a displacement of a laminated piezoelectric element, including: a valve main body having a gas pressure chamber that receives compressed gas supplied externally; and an actuator having a valving element, the laminated piezoelectric element that generates a driving force required for operating the valving element as the displacement, and a displacement enlarging mechanism that enlarges the displacement of the laminated piezoelectric element to be acted on the valving element, the actuator being disposed in the valve main body, in which a surface of the laminated piezoelectric element is coated with silicone in a state in which the laminated piezoelectric element is integrated into the actuator.

Abstract: Provided is a piezoelectric actuator that can reduce a risk of air leakage due to weakening of pressing force of a valve element against a valve seat surface and airtightness. The piezoelectric actuator is used for a piezoelectric valve that opens and closes a valve utilizing displacement of a laminated piezoelectric element. The piezoelectric actuator includes: a valve element; a laminated piezoelectric element that generates a driving force, required for operation of the valve element, as a displacement; and a displacement enlargement mechanism that enlarges a displacement of a laminated piezoelectric element and causes the enlarged displacement to act on the valve element. In the piezoelectric actuator, a surface of the valve element to be in contact with a valve seat of the piezoelectric valve is made flat and smooth in a state in which a tensile load is applied to the laminated piezoelectric element.

Abstract: In some examples, a system includes a magnet configured to move in response to a movement of a wear pin indicator of a brake assembly of a vehicle; and a sensor configured to generate position data corresponding to the magnet, the position data indicating a relative linear position of the wear pin indicator, wherein the position data corresponds to an estimated remaining useful lifespan of the brake assembly. Additionally, the system includes an energy harvesting device configured to generate an electrical signal based on an operation of one or both of the brake assembly and the vehicle, wherein the energy harvesting device is configured to deliver at least a portion of the electrical signal to the sensor.

Abstract: An external defibrillator apparatus (10, 74) operates to deliver electrical shocks to the heart muscles of a patient using a self-contained piezoelectric power source. The apparatus has a body (12) which includes a handle portion (26) in fixed operative connection with disposed paddle portions (14, 16). Each paddle portion includes a respective electrode (22, 24). Manual movement of a trigger (28, 78) is operative to cause circuitry (32, 82) which includes a piezoelectric crystal (34) to develop sufficient electrical potential between the electrodes to deliver the electrical shocks to the heart muscles through external contact with the patient's chest.

Abstract: A light-emitting module structure comprises a support substrate and a micro-module disposed on or in the support substrate that extends over only a portion of the support substrate. The micro-module comprises a rigid module substrate, an inorganic light-emitting diode, a power source, and a control circuit. The inorganic light-emitting diode, the power source, and the control circuit are disposed on or in the module substrate and the control circuit receives power from the power source to control the inorganic light-emitting diode to emit light. A light conductor is disposed on or in the support substrate and in alignment with the micro-module so that the inorganic light-emitting diode is disposed to emit light into the light conductor and the light conductor conducts the light beyond the micro-module to emit the light from the light conductor.

Abstract: Various embodiments include a mechanical amplification mechanism in a compact power unit of an electricity generator containing at least one piezoelectric element. The power units can be used singly but are also designed to be stacked, serially and/or in parallel with each other, and to be mounted within or under a substrate (e.g., a roadway or aircraft runway) such that the system achieves ultra-high-density of electricity production per unit area. Embodiments of the disclosed subject matter are therefore directed to a mechanical-to-electrical power generator, an accompanying power electronic-circuit, and power transmission and/or power saving into an energy-storage device. Therefore, the generated electrical power can be conditioned for, for example, transmitting to an electrical grid or for charging batteries of electrical vehicles. Other methods of formation of the power units and related systems are disclosed.

Abstract: In an example, an energy harvesting system includes a support apparatus and a piezoelectric element. The piezoelectric element may be configured as a plate supported at its periphery by the support apparatus to enable a central portion of the piezoelectric element to move along an axis that is orthogonal to a contact surface of the plate. A body having a mass is configured to move in a direction that is substantially parallel to the axis of the plate and apply force to deform the contact surface of the plate, such that electrical energy is generated by the piezoelectric element based on the applied force.

Abstract: A piezoelectric energy harvester has a layered structure comprising a first electrode, a polymeric piezoelectric material, and a second electrode, the layered structure coupled to receive mechanical stress from the environment, and the first and second electrode electrically coupled to a power converter. The power converter is adapted to charge an energy storage device selected from a capacitor and a battery. The method of harvesting energy from the environment includes providing a piezoelectric device comprising a layer of a polymeric piezoelectric material disposed between a first and a second electrode; coupling mechanical stress derived from an environment to the piezoelectric device; and coupling electrical energy from the piezoelectric device.

Abstract: It is an object of the present invention to array and utilize piezoelectric generators. It is also an object of the invention to implement properly configured piezoelectric generators into applications that can recapture expelled kinetic energy that is otherwise wasted. Particularly, piezoelectric generators, or arrays, may be, for example, placed in shoes, clothing, tires, roads, and sidewalks in order to recapture the energy expelled in everyday human activities (e.g., walking, moving, and driving).

Abstract: A suspension assembly provides a suspension frame and a supporting frame, the suspension frame being movably coupled to the supporting frame. The suspension assembly further provides at least one flexure that links the suspension frame to the supporting frame. The suspension assembly including at least one stopper to limit movement of the supporting frame and the suspension frame with respect to each other.

Abstract: A power supply circuit that outputs an electric power input from a vibration-driven energy harvesting element to an external load includes a rectifying circuit that rectifies an alternating current power input from the vibration-driven energy harvesting element; a first capacitor that accumulates a power output from the rectifying circuit; a chopper circuit that has a switching element controlling a chopper timing and has an input terminal connected to the first capacitor; and a control signal generation unit that supplies a control signal to the switching element, wherein: the control signal generation unit generates the control signal without referring to a voltage of the first capacitor.

Abstract: An emergency alarm system peripheral, such as a hazard detector, intrusion detector, or a notification appliance, includes a base that is permanently installed on a wall or ceiling, and a head which mounts to the base. Various embodiments and methods are provided to easily and efficiently assign addresses to the peripherals in the system.

Abstract: This document describes techniques and apparatuses directed at localized haptic feedback in electronic devices using pressure-sensitive adhesive (PSA) and piezoelectric haptic actuators. In aspects, an electronic device includes a housing having a frame defining a slot. An actuator is adhered to the frame at the bottom of the slot by the PSA. When a force is applied to an exterior surface of the actuator (“button press”), the PSA compresses and an extending member attached to the actuator, opposite the exterior surface, slidably moves within an aperture in the frame at the bottom of the slot. The extending member engages a sensor module (e.g., piezoelectric sensor) and the electronic device registers a button press. The sensor module then applies haptic feedback to the extending member and through the actuator to the exterior surface. When the force is removed from the actuator's exterior surface, the PSA expands to an approximate original thickness.

Abstract: A contact sensor for the repeatable detection of small, high frequency mechanical vibrations in external systems is presented herein. The sensor includes a metal housing with an attachment device at one end and an output at the other end. Inside the metal housing is a core assembly that includes a piezo transducer assembly suspended or isolated between an actuator and a biasing device. The actuator may be in the form of a ceramic sphere that sits at least partially within a recess on the inside of the housing and is in physical contact with the piezo transducer assembly. The biasing device may be in the form of a spring that causes the piezo transducer assembly to be pressed against the actuator at a contestant and known amount of tension.

Abstract: A vibrational energy harvester element includes: a first electrode; a second electrode that moves in a predetermined direction with respect to the first electrode; a third electrode; a fourth electrode that moves in the predetermined direction with respect to the third electrode; and a support portion that supports the second electrode and the fourth electrode so that they are movable along the predetermined direction; and wherein: the first electrode and the third electrode are disposed along the predetermined direction; at least one of facing surfaces of the first electrode and the second electrode, and at least one of facing surfaces of the third electrode and the fourth electrode, are electrically charged; and the support portion supports the second electrode and the fourth electrode in a state in which electrostatic force between the first electrode and the second electrode, and electrostatic force between the third electrode and the fourth electrode are balanced along the predetermined direction.

Abstract: The present invention is directed to a power bank with the capability to harvest electric energy which is then configured to charge its onboard battery such that the power bank is self-recharging. The energy harvesting power bank has an internal area provided with a piezoelectric mass suspended within a suspension frame by resilient members. The internal area is lined with piezoelectric film that is impacted by the piezoelectric mass as a result of the kinetic energy derived from movement of the power bank. As a consequence, the piezoelectric materials will generate electrical energy which will undergo conditioning by energy harvester electronics. The conditioned electrical energy is used to provide power to the USB charging port for use in recharging portable devices.

Abstract: A nozzle for mitigating against solvent flashing in a solvent-assisted hydrocarbon extraction process comprises a fluid passage extending between an inlet and an outlet, wherein the fluid passage comprises a converging region, a throat, and a diverging region, and wherein at least the converging region is provided with a gradually reducing internal diameter. Preferably, the angle of convergence of the converging region is equal to or less than about 5 degrees.

Abstract: A nozzle for controlling the flow of fluids into and/or out of a hydrocarbon-bearing reservoir comprises a fluid passage extending between first and second openings. The passage comprises a flow adjusting region for increasing the velocity of fluids injected into the reservoir and for choking steam produced from the reservoir.

Abstract: A charging circuit and a method with an inductor, an input to receive an input voltage, an output, and a switching means is presented. The switching means performs cycles where each cycle includes, switching the circuit such that the inductor enters into an energy charging state in which the inductor stores energy provided by the input voltage. When energy stored in the inductor reaches an energy threshold, the switching circuit operates such that the inductor enters into an energy discharging state in which the inductor provides energy to the output. The energy threshold is based on a predefined maximum energy storage current value and the time between cycles is based on a duration of the energy discharging state.

Abstract: A piezoelectric transformer and a method for producing a piezoelectric transformer are disclosed. In an embodiment, the method includes manufacturing a main body having an input region having electrodes and a first piezoelectric material being alternately stacked one on top of the other. An output region includes a second piezoelectric material. The first piezoelectric material is polarized and a removable contact is fitted to an output-side end side of the main body, which end side faces away from the input region. A first electrical potential is applied to the removable contact for polarizing the second piezoelectric material.

Abstract: Provided is an apparatus comprising a conductive particle interconnect (CPI). The CPI includes an elastomeric carrier and a plurality of conductive particles dispersed therein. The elastomeric carrier includes an electroactive polymer (EAP) configured to move between a first position and a second position in response to an electrical field. The CPI is configured to exhibit a first electrical resistance when the EAP is in the first position and a second electrical resistance when the EAP is in the second position. The apparatus further comprises one or more electrodes electrically coupled to the CPI. The electrodes are configured to generate the electrical field within the CPI. The apparatus further comprises one or more insulators coupled to the CPI. The one or more insulators are configured to constrain expansion of the CPI in at least one direction.

Abstract: Disclosed herein is a photoelectric sensor, display panel and their manufacturing method. The photoelectric sensor may comprise a photodeformable unit and a piezoelectric unit in contact with the photodeformable unit.

Abstract: An apparatus comprising: an image processor configured to determine at least one image parameter with respect to at least one image displayed on at least one display; a touch controller configured to determine at least one touch parameter with respect to the at least one display configured to display the at least one image; and a tactile effect generator configured to generate at least one tactile signal based on the at least one touch parameter and the at least one image parameter.

Abstract: In one or more embodiments, an apparatus generally comprises a microelectromechanical system (MEMS) module comprising a plurality of air movement cells and a power unit operable to control the plurality of air movement cells, and a housing configured for slidably receiving the MEMS module and positioning the MEMS module adjacent to a heat generating component of a network device. The MEMS module is operable to dissipate heat from the heat generating component and is configured for online installation and removal during operation of the heat generating component.

Abstract: A coversheet layer of an information handling system, comprising a coversheet having a key location of a haptic keyboard and a haptic touchpad area on a C-cover for the information handling system including a magnet or ferromagnetic insert in the coversheet for alignment to a top replaceable overlay layer magnetically attachable to the coversheet, a support layer, a contact foil placed between the coversheet and support layer, a piezoelectric element placed between the contact foil and support layer to receive an applied mechanical stress at the key location or touchpad actuation location of the coversheet and generate an electric actuation signal and a controller of the information handling system operatively coupled to the contact foil to receive the electric actuation signal and send an electrical haptic response signal to the piezoelectric element to cause the piezoelectric element to generate haptic feedback.

Abstract: The present disclosure discloses a power management circuit and a power management method for a triboelectric nanogenerator. The power management circuit includes a pulse current control switch, an intermediate energy storage element, and a target energy storage element, wherein the pulse current control switch is configured to instantaneously connect two electrode layers of the triboelectric nanogenerator to generate a transient pulse current, after movement of two relative moving components of the triboelectric nanogenerator generates static charges induced between the two electrode layers; the intermediate energy storage element is configured to store electric energy of the transient pulse current, and the target energy storage element is configured to store the electric energy output from the intermediate energy storage element.

Abstract: 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.

Abstract: A mechanical frequency upconverter includes a body having a cavity. A low-frequency membrane is coupled to the body and arranged adjacent to the cavity. The low-frequency membrane is a permanent magnet or a permanent magnet is affixed to the low-frequency membrane. A high-frequency membrane is coupled to the body and arranged adjacent to the cavity. The high-frequency membrane includes a magnetic metal. Oscillation of the low-frequency membrane at a first frequency causes the high-frequency membrane to oscillate at a second frequency, which is higher than the first frequency.

Abstract: Wireless power transmission (WPT) systems are provided. For example, the WPT system can use one or more power transmitting coils and a receiver for electromagnetically coupled wireless power transfer. The electrodynamic receiver can be in the form of an electrodynamic transducer where a magnet is allowed to oscillate near a receiving coil to induce a voltage in the receiving coil, a piezoelectric transducer where the magnet causes a vibrating structure with a piezoelectric layer to move, an electrostatic transducer where movement of the magnet causes a capacitor plate to move, or a combination thereof. An alternating magnetic field from the transmitting coil(s) excites the magnet in the receiver into mechanical resonance. The vibrating magnet then functions similar to an energy harvester to induce voltage/current on an internal coil, piezoelectric material, or variable capacitor.

Abstract: Provided are: a power generator including a dielectric elastomer element with an elastomer layer and electrodes sandwiching the layer; an intermediate power storage including a specific number of capacitors to receive output power from the power generator; a storage unit to receive output power from the intermediate power storage; and a controller for setting control by switching a mode between an input mode and an output mode. In the input mode, some number of the capacitors of the intermediate power storage are connected to the power generator such that a series number is an input series number of less than or equal to the specific number. In the output mode, some number of the capacitors are connected to the storage unit such that the series number is an output series number which is smaller than the input series number.

Abstract: A circuit element. In some embodiments, the circuit element includes a first terminal, a second terminal, and a layered structure. The layered structure may include a first conductive layer connected to the first terminal, a first piezoelectric layer on the first conductive layer, a second piezoelectric layer on the first piezoelectric layer, and a second conductive layer connected to the second terminal. The first piezoelectric layer may have a first piezoelectric tensor and a first permittivity tensor, and the second piezoelectric layer may have a second piezoelectric tensor and a second permittivity tensor, one or both of the second piezoelectric tensor and a second permittivity tensor differing, respectively, from the first piezoelectric tensor and the first permittivity tensor.

Abstract: A piezoelectric transducer includes an anchorage and a beam of semiconductor material extending in cantilever fashion from the anchorage in a main direction parallel to a first axis and having a face parallel to a first plane defined by the first axis and by a second axis perpendicular to the first axis. A piezoelectric layer is on the face of the beam. A cross-section of the beam is perpendicular to the first axis and is asymmetrical and shaped so the beam deformations out of the first plane in response to forces applied to the anchorage and oriented parallel to the first axis.

Abstract: In one embodiment, a system for determining strain within a material includes a magnetostrictive sensor configured to be embedded within the material, a sensing unit configured to apply an excitation magnetic field to the material and the embedded sensor and to receive a response magnetic field that has passed through the material and the embedded sensor, wherein the sensing unit does not contact the material, and a device configured to determine a difference between the excitation magnetic field and the response magnetic field and to determine the strain within the material based upon that difference.

Abstract: A power generation device includes a rotatable member arranged to rotate about a rotating axis in response to an application of force; and at least one power generation unit including at least one deformable member, the deformable member arranged to deform for generating electrical energy in response to the rotation of the rotatable member. The present invention also discloses a power generation device having an oscillatable member and an electric device incorporating the power generation device.

Abstract: Methods, systems, and devices are disclosed for implementing a stretchable nanoparticle-polymer composite foams that exhibit piezoelectric properties. In one aspect, a nanoparticle-polymer composite structure includes a curable liquid polymer; piezoelectric nanoparticles; and graphitic carbons.

Abstract: A traffic regulation system and method which combines energy harvesting from the movement of a plurality of vehicles on a roadway with wireless directional power beam transmission using the harvested energy to encourage compliance with traffic regulations. Electric power is generated from the movement of the moving vehicles by using a wind turbine to harvest wind energy from the movement of vehicles or by piezoelectric plates which harvest compression energy from the weight of the vehicle tires on the road surface. The electric power is transmitted to electric or hybrid vehicles which comply with the traffic regulations. The traffic regulations are one of driving at a posted speed and driving at a safe following distance. A control system adjusts the traffic regulation based on measurements received from a plurality of detectors.

Abstract: The present disclosure relates to novel triboelectric nanogenerators with flexible polymeric dielectric layer comprising liquid metal particles, and method of making and using the novel triboelectric nanogenerators.

Abstract: An external rear view device for a motor vehicle includes a casing which has at least one part made from a polymer, wherein the at least one part of the casing comprises piezo-electrical particles and at least one conductive element which is in electrical contact with the piezo-electrical particles and inductively coupled to a power storage unit. A motor vehicle with such a rear view device is also described.

Abstract: An electric power generator for a projectile moving through the air is based on vibrational, rather than rotational motion. The electric power generator uses an air stream through, which the projectile is traveling typically 100-250 m/s for mortars to up to 1,500 m/s for sabot or even higher electrically fired rounds. A typical 223 rifle round after being fired has energy of over 1700 J, which is equivalent to 1700 W seconds. If a Nano computer was able to extract energy of for example 50 nanowatts during bullet flight which rarely exceeds two seconds the power needed during the flight would be only a few parts per billion of the bullets energy. Even allowing for very inefficient extraction of power, the necessary power to operate on onboard electronic devices such as computers and sensors can be extracted from the airstream through which the projectile travels.

Abstract: According to the present invention there is provided a button assembly, comprising, an actuator member; a base member having a cavity defined therein which can receive a least a part of the actuator member; a flexible film which comprises piezoelectric material, wherein the piezoelectric material is preferably dipolar particles; a first electrode which is located between the piezoelectric material of the flexible film and the actuator member, and a second electrode which is located between the piezoelectric material of the flexible film and the base member, and wherein the flexible film is arranged to overlay the cavity in the base member, and to be interposed between the base member and the actuator member, such that moving at least a part of the actuator member into the cavity of the base member will cause the film to stretch thereby generating an electrical signal in the first and second electrodes.

Abstract: A method of on-demand energy delivery to an active suspension system comprising an actuator body, hydraulic pump, electric motor, plurality of sensors, energy storage facility, and controller is provided. The method comprises disposing an active suspension system in a vehicle between a wheel mount and a vehicle body, detecting a wheel event requiring control of the active suspension; and sourcing energy from the energy storage facility and delivering it to the electric motor in response to the wheel event.

Abstract: A traffic regulation system and method which combines energy harvesting from the movement of a plurality of vehicles on a roadway with wireless directional power beam transmission using the harvested energy to encourage compliance with traffic regulations. Electric power is generated from the movement of the moving vehicles by using a wind turbine to harvest wind energy from the movement of vehicles or by piezoelectric plates which harvest compression energy from the weight of the vehicle tires on the road surface. The electric power is transmitted to electric or hybrid vehicles which comply with the traffic regulations. The traffic regulations are one of driving at a posted speed and driving at a safe following distance. A control system adjusts the traffic regulation based on measurements received from a plurality of detectors.

Abstract: An energy harvesting device for generating electrical power from low-frequency oscillations includes a high-frequency cantilever, a plurality of low-frequency cantilevers each configured to contact the high-frequency cantilever in response to environmental vibrations having a frequency within a near-resonance frequency range associated with said low-frequency cantilever, an a generator that produces electrical power in response to contact between at least one of the plurality of low-frequency cantilevers and the high-frequency cantilever. The energy harvesting device may also include an impact mass coupled to a free end of each of the plurality of low-frequency cantilevers. Some aspects may include a common base to which the high-frequency cantilever and the plurality of low-frequency cantilevers are coupled. Other aspects may include the generator comprising one or more of an induction coil and magnet, a variable distance capacitor, or a piezo-electric material.