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420 results about "Piezoelectric transduction" patented technology

Energy harvesting acoustic metasurface using piezoelectric transducers

The technology described herein is directed towards resonators that incorporate or are closely coupled to transducers from which energy is harvested. The resonators can be unit cells of a metasurface configured for narrowband sound absorption by phase cancellation of the acoustic wave Electroacoustic transducers such as piezoelectric transducers can be positioned, e.g., at the neck ports of the resonators, to generate electricity as the air pressure of incoming acoustic waves enters the unit cells. Energy can be harvested from the electricity, and stored for usage and / or used directly to power a device. Such a device powered by the harvested energy can change the resonant frequency of the device, e.g., by changing temperatures in the resonators' air cavities, changing respective dimensions of the respective air cavities, or changing the resonant frequency of the unit cells resonators by changing respective airflow in the respective air cavities.
Owner:DELL PROD LP

Method, system, equipment and medium based on multi-composite ultrasonic penetration technology

The invention discloses a method, a system, equipment and a medium based on a multi-composite ultrasonic penetration technology, and the method comprises the steps: generating high-frequency fundamental ultrasonic waves through a piezoelectric transducer array, and adjusting the frequency range to match the acoustic impedance characteristic of target soil; first, second and third harmonics are generated through the induction of a nonlinear medium in the fundamental wave propagation process, the phases of the harmonics are adjusted to realize coherent superposition, and the fundamental wave and the first, second and third harmonics are guided into a composite waveguide device for focusing and delay compensation to form a high-energy composite wave beam; a pulse interval is adjusted by adopting an intermittent emission strategy so as to inhibit energy attenuation in the soil; reflected wave spectrum components are monitored through an embedded acoustic sensor array, and driving parameters are dynamically adjusted; and residual ultrasonic energy is captured and fed back to a driving circuit to form a closed-loop energy utilization system. By integrating multi-order harmonic resonance and a dynamic frequency tuning technology, efficient transmission and deep penetration of ultrasonic energy in a complex medium are realized.
Owner:GUANGXI POWER GRID CORP

Multi-modal fusion pipeline damage positioning method

The invention relates to a multi-modal fusion pipeline damage positioning method, which comprises the following steps of: uniformly arranging piezoelectric transducer arrays along the circumferential direction of a pipeline, generating non-frequency dispersion L (0, 2) and T (0, 1) guided waves respectively excited by 70kHz sine pulses as excitation signals, and unidirectionally spreading the excitation signals along the pipeline; the method comprises the following steps: acquiring reflection echoes at a to-be-measured section of a pipeline, and performing matched filtering, omega-k domain filtering and circumferential modal decomposition on the reflection echoes to obtain two modal components in an L (0, 2) mode and a T (0, 1) mode; performing back propagation and focusing imaging on each modal component to obtain imaging results under two modals L (0, 2) and T (0, 1); and fusing the imaging results in the two modals to obtain a multi-modal fusion pipeline damage image. Compared with the prior art, the method has the advantages that the problem that sensitivity of different defect types is difficult to consider due to single-mode optimization and the problems of signal waveform distortion and energy dispersion existing in multi-mode signals are solved.
Owner:EAST CHINA UNIV OF SCI & TECH

Selectively insulated ultrasound transducers

Disclosed herein are ultrasound transducers that are selectively insulated to thereby enable the transducers to be exposed to an electrically conductive fluid without causing a short circuit between electrodes of the transducers. Such a transducer includes a piezoelectric transducer body having a first surface and a second surface that are spaced apart from one another and do not intersect with one another. The ultrasound transducer also includes a first electrode disposed on the first surface, a second electrode disposed on the second surface, and an electrical insulator covering only one of first and second electrodes and configured to inhibit electrical conduction between the first electrode and the second electrode when the ultrasound transducer is placed within an electrically conductive fluid. Also disclosed are apparatuses and systems that include such a transducer. Related methods are also disclosed herein.
Owner:OTSUKA MEDICAL DEVICES

Graphene oxide flow stripping and closed-loop regulation and control system and method driven by ultrasonic phased array

The invention discloses an ultrasonic phased array driven graphene oxide flow stripping and closed-loop regulation and control system and method, and the system comprises an ultrasonic phased array module, and a piezoelectric transducer array element in the ultrasonic phased array module controls sound beam focusing and energy distribution through a phase delay controller, and carries out the stripping of graphite oxide flowing in a flow channel; a micro-Raman spectrometer in the micro-fluidic-Raman detection module collects characteristic peak data of a graphene oxide sheet layer in a micro-fluidic chip in real time and sends the characteristic peak data to a signal analysis unit; and the feedback control module is used for receiving the layer number distribution data output by the signal analysis unit, dynamically adjusting ultrasonic parameters of the phase delay controller, and controlling the diverter valve to guide substandard products into a secondary treatment channel and finally return the substandard products to the flow channel for stripping again. The system and the method for stripping the graphene oxide based on coupling of the ultrasonic phased array and the micro-fluidic chip have the advantages of efficient stripping, accurate detection, closed-loop optimization and the like.
Owner:HUNAN SMART VALLEY NEW ENERGY TECHNOLOGY RESEARCH INSTITUTE CO LTD

System for chip-removing machining of a workpiece and for measuring and evaluating force and torque during chip-removing machining of the workpiece

A system for chip-removing machining of a workpiece and for measuring and evaluating force and torque during the chip-removing machining of the workpiece includes a machine tool with a tool for chip-removing machining of the workpiece; a device for measuring force and torque that includes a plurality of piezoelectric transducers generating polarization charges being communicated through a respective measuring channel; and a stationary evaluation unit for evaluating measured value data of the device. The device includes a measuring unit installed in the machine tool and rotates with the tool about an axis of rotation during chip-removing machining. The device includes a control unit that transmits measured values as measured value data in a wireless manner directly to the evaluation unit with a transmission power in the range of 0.1 mW to 10 mW.
Owner:KISTLER HLDG AG

Multi-medium sound field control system based on AI algorithm

The invention discloses a multi-medium sound field control system based on an AI algorithm, which belongs to the field of intelligence and comprises a data acquisition module, a sound field modeling module, an AI optimization control module, a self-adaptive adjustment module, a hardware execution module and the like. The data acquisition module is used for sampling and acquiring acoustic signals in air, water and a solid medium; the sound field modeling module is combined with a finite difference time domain method and a graph neural network to accurately simulate sound wave propagation; the AI optimization control module fuses near-end strategy optimization and a differential evolution algorithm to generate an optimal excitation parameter; the adaptive adjustment module is based on a model migration and contrast learning mechanism; the hardware execution module generates a controllable sound field by using a piezoelectric transducer array; and the feedback evaluation module passes back measurement data through laser vibration measurement and a microphone array to realize closed-loop correction of control parameters. The method has the advantages that high-precision sound wave modeling, intelligent control parameter optimization and dynamic self-adaptive adjustment capacity are achieved, and the real-time performance, stability and the like of sound field control in the multi-medium environment are improved.
Owner:SHANGHAI JUNJI INTELLIGENT TECH CO LTD

Uniform tin droplet target generating device for inhibiting axial shaking of tin droplets

The invention provides a uniform tin droplet target generating device for inhibiting axial shaking of tin droplets, which comprises a crucible, tin melt, a nozzle, a heating assembly and a disturbance assembly, the tin melt is located inside the crucible, and the heating assembly is located outside the crucible and is used for heating the tin melt in the crucible; the nozzle is located at the bottom of the crucible and used for spraying uniform tin liquid drops and reducing axial shaking of the tin liquid drops. The disturbance assembly comprises a signal generator, a piezoelectric transducer and a vibration transmission rod, the vibration transmission rod is located in the molten tin, the piezoelectric transducer is located above the crucible and connected with the vibration transmission rod through a connecting piece, and the signal generator is connected with the piezoelectric transducer; a sine disturbance signal generated by the signal generator is provided for the vibration transmission rod through the piezoelectric transducer, and the disturbance signal is transmitted into molten tin through the vibration transmission rod, so that the jetted tin jet flow is broken into uniform liquid drop flow; according to the device provided by the invention, the distance between the liquid drops can be regulated and controlled; the designed nozzle can reduce the axial jitter of the liquid drop flow and increase the axial stability of the liquid drop.
Owner:NORTHWESTERN POLYTECHNICAL UNIV

System for generating large water drops and control strategy

The invention belongs to the technical field of fluid control and atomization, and particularly relates to a main control system, a liquid supply system, a generation system and an auxiliary system. The generating system comprises a water storage tank, a porous steel sheet arranged at the bottom of the water storage tank, conical micropores formed in the porous steel sheet, a piezoelectric transducer fixed to the bottom of the porous steel sheet, a soaking copper plate arranged at the top of the water storage tank and an electric heating layer installed on the soaking copper plate. Due to the fact that an existing annular transducer cannot meet the requirement for generation of a single water drop or multiple water drops and cannot meet the requirement for accurate and controllable sizes of the water drops, a rectangular transducer pair is adopted as an excitation device, surface wave superposition can be generated through vibration of the transducer, meanwhile, the liquid level of a water storage tank is controllable, and the energy storage efficiency is improved. High-temperature pulses are applied to the air layer on the upper surface of the water layer, so that the pressure in the water tank is controllable during spraying, and inconsistent diameters of water drops caused by uncontrollable pressure are avoided.
Owner:LIYANG PNEUMATIC INNOVATION RES INST CO LTD

Ultrasonic fingerprint identification method, chip, system, electronic equipment and storage medium

The invention discloses an ultrasonic fingerprint identification method, a chip, a system, electronic equipment and a storage medium, and the method comprises the steps: controlling an ultrasonic piezoelectric transducer to work based on first configuration information, and obtaining one or more first fingerprint images; performing spatial frequency identification on the one or more first fingerprint images, and determining a first spatial frequency corresponding to the one or more first fingerprint images; when one or more first fingerprint images meet the adaptive condition, determining second configuration information based on the first spatial frequency and the first configuration information; and updating the first configuration information by adopting the second configuration information. According to the method, the first configuration information is dynamically adjusted based on the first spatial frequency corresponding to the first fingerprint image, so that the adjusted second configuration information can effectively guarantee the overall performance of the ultrasonic fingerprint system, the quality of the fingerprint image acquired subsequently is improved, the recognition effect is improved, and the universality of the system is improved.
Owner:SHENZHEN GOODIX TECH CO LTD

Ultrasonic guided wave edge real-time communication method and system based on FPGA

The invention specifically discloses an ultrasonic guided wave edge real-time communication method and system based on an FPGA (Field Programmable Gate Array), and the method comprises the following steps: the FPGA of a guided wave communication transmitting circuit receives data needing to be transmitted, completes the data package construction and carrier modulation, and outputs a digital signal; after digital-to-analog conversion, a multi-stage power amplification circuit and a matching network circuit, the ultrasonic guided waves are transmitted to an excitation piezoelectric transducer, and the excitation piezoelectric transducer generates ultrasonic guided waves to be transmitted in a metal medium; the receiving piezoelectric transducer converts ultrasonic guided waves transmitted in a metal medium into piezoelectric signals, the piezoelectric signals sequentially pass through the active filter circuit, the variable gain amplification circuit and the analog-to-digital conversion circuit and are transmitted to the FPGA of the guided wave communication receiving circuit in the form of digital quantity, and the FPGA operates a demodulation algorithm to restore effective binary data. And the data is transmitted to other equipment. According to the technical scheme, the FPGA serves as a processing unit, high-frequency carrier modulation and real-time operation of a complex demodulation algorithm can be completed, and the high-speed communication requirement can be met.
Owner:CHONGQING UNIV

Stretchable ultrasonic transducer devices

A conformable piezoelectric transducer array for performing ultrasound or the like includes a silicone elastomer substrate and a silicone elastomer superstrate. A plurality of piezoelectric transducer elements are disposed between the substrate and superstrate. A first electrical interconnect layer electrically interconnects a first surface of the transducer elements adjacent to the substrate and a second electrical interconnect layer electrically interconnecting a second surface of the transducer elements adjacent to the superstrate.
Owner:RGT UNIV OF CALIFORNIA

Bulk acoustic wave resonator, filter and electronic equipment

The invention provides a bulk acoustic wave resonator, a filter and electronic equipment. The bulk acoustic wave resonator comprises a substrate layer, a Bragg reflection layer arranged on the substrate layer and a piezoelectric transduction structure layer arranged on the Bragg reflection layer. The Bragg reflection layer comprises a plurality of film layers which are arranged in a stacked mode, and the refractive indexes of every two adjacent film layers are different; the piezoelectric transduction structure layer comprises a piezoelectric layer and an electrode layer which are stacked; at least one film layer, close to the piezoelectric transduction structure layer, in the Bragg reflection layer is a preset film layer, the preset film layer comprises cavity parts and supporting parts, the cavity parts and the supporting parts are alternately arranged in the first direction, and the first direction is parallel to the substrate layer. According to the bulk acoustic wave resonator, acoustic wave energy is concentrated on the piezoelectric layer through the cavity parts, the electromechanical coupling coefficient of the bulk acoustic wave resonator is increased, under the alternate arrangement of the cavity parts and the supporting parts, the slowness curve of the main vibration mode of the bulk acoustic wave resonator is flattened, the transverse mode and stray response are restrained, and therefore the quality factor of the bulk acoustic wave resonator is improved.
Owner:HUAWEI TECH CO LTD

Acoustophoretic analyzation devices and methods

Fluid analyzation devices, methods, and systems are disclosed including an analyzation device comprising a sample vessel having an outer surface, a microchannel within the confines of the outer surface, a first port extending through the outer surface to the microchannel, and a second port extending through the outer surface to the microchannel; and an piezo transducer bonded to the outer surface of the sample vessel to form a monolithic structure, the piezo transducer configured to emit ultrasonic acoustic waves having a first frequency, a second frequency, and a third frequency into and / or to a blood sample within the microchannel, the first frequency configured to begin separation of red blood cells and plasma in the blood sample, the second frequency configured to complete separation of the red blood cells and plasma, and the third frequency configured to rupture cell walls of the blood cells producing a lysed blood sample.
Owner:SIEMENS HEALTHCARE DIAGNOSTICS INC

Longitudinal bending composite type six-degree-of-freedom piezoelectric active vibration isolation platform and working method thereof

The invention discloses a longitudinal bending composite type six-degree-of-freedom piezoelectric active vibration isolation platform and a working method thereof. The vibration isolation platform adopts a modular structural design, a vibration isolation connecting platform and a base platform are sequentially arranged from top to bottom and are connected through four uniformly distributed vibration isolation modules, and each vibration isolation module forms a multi-stage vibration transmission structure through a fixed base, a transducer base, a piezoelectric transducer, an amplitude-change pole, a pre-tightening bolt and a small flexible hinge. The control module collects feedback signals of a first acceleration sensor arranged on the vibration isolation connecting platform and feedforward signals of a second acceleration sensor arranged on the base platform, and outputs 12-channel control signals to the piezoelectric transducers of the vibration isolation modules after signal processing. The piezoelectric transducer is driven to generate a composite motion mode of longitudinal vibration and multidirectional bending vibration, and active suppression of longitudinal vibration and radial bending vibration in any direction of a vibration isolation object is achieved. The device has the advantages of multi-degree-of-freedom vibration isolation, compact structure, lightweight design, independent control, high stability and the like, and has important application value in the fields of space reflecting mirrors, micro-nano manufacturing equipment vibration control and multi-degree-of-freedom vibration isolation systems.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Double-cantilever-beam piezoelectric vibration energy collector based on annular steady state

The invention discloses a double-cantilever-beam piezoelectric vibration energy collector based on an annular steady state, which comprises a piezoelectric transducer, an elastic cantilever beam, a magnet and a base, after the piezoelectric transducer is mounted on the elastic cantilever beam to form a double-layer composite cantilever beam, the magnet is mounted at the free end of the double-layer composite cantilever beam, nonlinear coupling is carried out through repulsive magnetic force, and the piezoelectric transducer is connected with the base. The two-dimensional annular potential well structure with the adjustable potential well is formed, and the energy collector can easily trigger large-amplitude inter-well movement through the potential well structure. Through the nonlinear coupling induced internal resonance effect, inter-well energy transfer and two-dimensional potential well modulation are realized, and vibration energy can be efficiently captured in a broadband without a large amount of energy input or a complex structure. According to the design, the collection efficiency of low-frequency, low-intensity and multi-direction environment vibration energy in a wide working bandwidth is good.
Owner:SOUTHEAST UNIV

Apparatus for Mitigating Contamination in Fuel Tanks

An apparatus for mitigating contamination in a fuel supply is an ultrasonic generator coupled with a piezoelectric transducer that propagates ultrasonic waves through a fuel tank. In some embodiments the apparatus is used to mitigate the growth of microbial organisms. In other embodiments the apparatus is used to emulsify water into the fuel, particularly in diesel fuel. The apparatus addresses water and microbial growth found in boats, cars, and aircraft as well as in storage tanks such as those used at fuel stations. In some embodiments, the fluid is diesel fuel.
Owner:LOCCISANO VINCENT

Planetary regolith dust expulsion for structures and surfaces using piezoelectric assembly induced vibration

A system is provided including one or more piezoelectric assemblies, where the one or more piezoelectric assemblies include a plurality of piezoelectric transducers. The system includes amplifier circuitry coupled to the plurality of piezoelectric transducers and configured to provide an alternating-current (AC) voltage signal to one or more piezoelectric transducers of the plurality of piezoelectric transducers, based on a target configuration associated with removing regolith dust from a vehicle operable in a space environment. The one or more piezoelectric transducers are configured to vibrate based on a magnitude and a frequency of the AC voltage signal.
Owner:HAMILTON SUNDSTRAND CORP

Acoustic resonator, filter and electronic equipment

The invention provides an acoustic resonator, a filter and electronic equipment. The acoustic resonator comprises a substrate layer, a piezoelectric transduction structure layer and an energy adjusting layer, the piezoelectric transduction structure layer is arranged on one side of the substrate layer; the energy adjusting layer is arranged between the substrate layer and the piezoelectric transduction structure layer, the energy adjusting layer comprises a plurality of binding grooves, and each binding groove at least penetrates through the surface, facing the piezoelectric transduction structure layer, of the energy adjusting layer. Through the binding grooves which are arranged at intervals and penetrate through the surface, facing the piezoelectric transduction structure layer, of the energy adjusting layer, sound wave energy is concentrated on the piezoelectric transduction structure layer, leakage of the sound wave energy towards the substrate layer is reduced, and the electromechanical coupling coefficient of the acoustic resonator is improved; the piezoelectric transduction structure layer is supported, collapse of the piezoelectric transduction structure layer is avoided, the situation that the power capacity of the acoustic resonator is reduced is reduced, and therefore the power capacity and the electromechanical coupling coefficient of the acoustic resonator are improved.
Owner:HUAWEI TECH CO LTD

Self-cleaning ultrasonic sensors

Ultrasonic sensors, sensor controllers, and sensor control methods are provided with self-cleaning functionality. An illustrative method includes: driving a piezoelectric transducer to generate a short acoustic burst for obstacle detection or distance measurement; obtaining a receive signal to monitor for reflections of the short acoustic burst; and operating to clean the sensor by driving the piezoelectric transducer to generate a long acoustic burst at a resonant frequency of the piezoelectric transducer. The method may be implemented by a sensor controller having a transmitter configured to drive the piezoelectric transducer, a receiver coupled to the piezoelectric transducer and a microphone to detect a reflection of the acoustic burst within a measurement interval associated with the acoustic burst; and a microcontroller configured to control a length of the acoustic burst. The sensor controller may be incorporated into a sensor that also includes a piezoelectric transducer and optionally includes one or more microphones.
Owner:SEMICON COMPONENTS IND LLC

Ultrasonic parameter adaptive adjustment and cleaning evaluation method in wafer cleaning process

The invention provides an ultrasonic parameter adaptive adjustment and cleaning evaluation method in a wafer cleaning process, and relates to the technical field of semiconductor manufacturing, and the method comprises the steps: calculating sound field energy distribution through collecting wafer surface temperature distribution and cavity vibration response data; based on the temperature gradient and the sound intensity gradient, calculating the micro-flow field distribution of the cleaning fluid, and establishing a cavitation bubble collapse characteristic matrix; recognizing and cleaning a dead zone through singular value decomposition of the feature matrix, and controlling a piezoelectric transducer to generate focused ultrasonic waves; meanwhile, the plasma resonance sensor is used for monitoring the surface adsorption characteristic change and evaluating the cleanliness. According to the invention, real-time self-adaptive adjustment of ultrasonic cleaning parameters is realized, and the cleaning uniformity and efficiency are improved.
Owner:SHENZHEN ON XI GREEN ENERGY TECH

Estimation of scaling in objects by processing ultrasound responses using machine learning (ML)

Machine Learning based scaling estimation in the art mostly used a complex guided wave setup. Further, selection of features for ML is critical to the predict significant points on the US signal response providing appropriate but minimum features that capture maximum scaling characteristics, thus keeping the ML features minimal to provide time and resource efficient computation. A method and system for estimation of scaling in objects by processing ultrasound responses using ML is disclosed. The system uses low-voltage pulse packets to generate ultrasonic (US) waves, capable of penetrating metal structures, using an economically repurposed piezoelectric transducer. These US signal response from the object-scaling interface and scaling-fluid interface, is captured using the repurposed piezoelectric transducer and processed to generate the envelope of the US signal response, and unique 42 features are extracted. A pretrained ML model processes the features to estimate various levels of scaling present in the object.
Owner:TATA CONSULTANCY SERVICES LTD

Solid plate defect detection method based on Lamb wave end face echoes

The invention relates to the technical field of solid plate defect detection, in particular to a solid plate defect detection method based on Lamb wave end face echoes, which comprises the following steps: exciting and receiving wedge piezoelectric transducers are arranged on the same side of a solid plate, exciting and receiving a single-mode Lamb wave signal, and acquiring a multi-path signal comprising a direct wave, a side face echo and a defect reflection echo; by analyzing the difference between a direct wave and a side echo, a defect reflection signal is extracted, and by combining the time difference between the defect reflection signal and the side echo and the Lamb wave propagation speed, a geometric model is established, and the defect position is accurately calculated. By adjusting the position of a transducer, the time difference between a defect reflected wave and a direct wave is constant, a defect echo amplitude value is obtained under the equal propagation condition and compared with a standard test block amplitude value, a mapping relation between the amplitude value and the size is constructed, and accurate quantification of the defect size is achieved.
Owner:CHANGSHA AVIATION VOCATIONAL & TECH COLLEGE (AIR FORCE AVIATION MAINTENANCE TECH COLLEGE)

Sandwich type piezoelectric driven double-shaft output mobile robot and working method thereof

The invention discloses a sandwich type piezoelectric driving double-shaft output mobile robot and a working method thereof.The sandwich type piezoelectric driving double-shaft output mobile robot comprises a sandwich type piezoelectric transducer, a pre-pressure applying mechanism, a driving wheel unit, a first output shaft, a second output shaft, a base body frame and a connecting plate, and a clamping mechanism is not arranged on a stator base body of the sandwich type piezoelectric transducer; a single pin of the pre-pressure applying mechanism and a through hole in the middle of a stator node beam are used for restraining, automatic rolling transmission of contact force is achieved under the condition of matching of the pin hole, and pre-pressure transmitted by the pre-pressure applying mechanism achieves force balance under the counter-acting force generated when a first driving foot and a second driving foot of the sandwich type piezoelectric transducer make contact with the curved surface of an output shaft. The elliptical motion trail direction of the stator driving foot can be controlled by controlling the electric signal phase difference of the longitudinal vibration piezoelectric ceramic set and the bending vibration piezoelectric ceramic set, forward and reverse motion of the first output shaft and the second output shaft is achieved through friction contact, and the mobile robot achieves forward, backward and rapid locking motion.
Owner:NANJING UNIV OF AERONAUTICS & ASTRONAUTICS

Optoacoustic monitoring device for cell characterization

A monitoring device of biological cells including: a fluidic channel in which a fluid including biological cells is made to flow, including a first and second glass walls placed in parallel and a reflective surface adjoined to the second wall; and a piezoelectric transducer, the piezoelectric transducer emitting acoustic waves creating a force acting on the biological cells, making them flow substantially along a single motion plane. The external interface between the first wall and the exterior of the fluidic channel and the reflective surface are configured to function as a Fabry-Perot interferometer, such that the motion planes sensibly perpendicular to the optical axis of the Fabry-Perot interferometer. The finesse of the interferometer is lower than 10. The monitoring device further includes a detecting unit detecting a fringe pattern stemming from the Fabry-Perot interferometer and an analysing device, analysing the fringe pattern and configured to output data on physical properties of the cells based on the pattern.
Owner:UNIV COTE DAZUR +2

Piezoelectric transducers for detection of touch on a surface

Examples of the disclosure are directed to the use of one or more piezoelectric (PE) transducers for detecting one or more touches on a surface. In some embodiments, the one or more PE transducers can complement a capacitive touch sensor array and provide a confirmation that a touch has in fact occurred, and can provide a secondary determination of touch location. In some examples, the one or more PE transducers can be formed on, or as part of, a flex circuit that is adhered to a housing or other structure to which the touch surface is affixed. The flex circuit can be formed as a strip upon which the one or more PE transducers are attached, and can be shaped and sized (optionally with a fold to create a tail for electrical connections) to adhere to an inner or outer surface of the housing.
Owner:APPLE INC

Two-dimensional adjustable ultrasonic vibration assisted cutting device

The application relates to a two-dimensional adjustable ultrasonic vibration auxiliary cutting device which comprises a vibration flat plate, a supporting base, four supporting columns, a stepped horn a, a stepped horn b, a longitudinal vibration piezoelectric transducer a and a longitudinal vibration piezoelectric transducer b. The vibration flat plate is of a stepped structure. The four supporting columns are vertically arranged, the upper ends of the four supporting columns are fixedly connected with the four corners of the vibration flat plate respectively, and the lower ends of the four supporting columns are fixedly connected with the supporting base simultaneously. The stepped horn a and the stepped horn b are horizontally arranged. The small end of the stepped horn a is fixedly connected with the center position of the left side surface of the vibration flat plate perpendicularly, and the large end is fixedly connected with the longitudinal vibration piezoelectric transducer a. The small end of the stepped horn b is fixedly connected with the center position of the back side surface of the vibration flat plate perpendicularly, and the large end is fixedly connected with the longitudinal vibration piezoelectric transducer b. The device has the characteristics of simple structure, less energy dissipation and good machining stability, and can realize efficient and low-damage milling and pin machining.
Owner:SHANGHAI JIAOTONG UNIV +1

An ultrasonic cavitation microjet polishing module for polishing microstructures

This invention relates to the field of ultra-precision polishing technology, specifically to an ultrasonic cavitation microjet polishing module for polishing microstructures. The module includes an acoustic focusing nozzle, a center-penetrating piezoelectric transducer, an adaptive acoustic impedance frequency tracking system, and a liquid supply and bubble nucleation system. The acoustic focusing nozzle employs a variable cross-section acoustic amplitude rod structure, ensuring that the standing wave antinodes and nozzle outlet are confocal, thus increasing energy density. The piezoelectric transducer has a ring structure with fluid flowing through its center, achieving efficient energy conversion. The frequency tracking system adjusts the excitation frequency in real time to maintain resonance. The liquid supply system introduces cavitation nuclei through a venturi tube, reducing the cavitation threshold. This invention, through an acoustic-fluid coupling mechanism, utilizes the dual effects of macroscopic kinetic energy removal and microscopic cavitation removal to solve the problems of traditional polishing techniques, such as difficulty in processing high aspect ratio microstructures, incomplete bottom polishing, and low efficiency. It achieves high-precision polishing of microstructure surfaces, and is particularly suitable for ultra-precision machining of deep and narrow grooves.
Owner:JIANGSU YUDI OPTICAL CO LTD

Transparent ultrasonic transducer using beam shaping and assembly method thereof

A transparent ultrasonic transducer device for performing multi-mode optical imaging on a target object is provided. The device includes a transparent piezoelectric transducer, one or more conductive wires, and an optical lens. The transparent piezoelectric transducer having a first acoustic impedance is configured to receive acoustic waves from the target object. The transparent piezoelectric transducer has a first surface and a second surface. The first surface and the second surface are coated with a transparent conductive coating. The optical lens contacts the first surface of the transparent piezoelectric transducer and is optically coupled to the first surface. The optical lens is made of a material having a second acoustic impedance, and the first acoustic impedance and the second acoustic impedance are substantially similar to minimize acoustic impedance mismatch, thereby improving the sensitivity of the device.
Owner:THE HONG KONG POLYTECHNIC UNIV

Piezoelectric energy acquisition circuit based on parallel synchronous switch inductors

The invention discloses a piezoelectric energy acquisition circuit based on a parallel synchronous switch inductor, which comprises n piezoelectric transducers, n rectification circuits, n peak detection modules, an inductor, a first diode and an energy storage capacitor, and is characterized in that each piezoelectric transducer acquires vibration energy, converts the vibration energy into alternating voltage and outputs the alternating voltage; each rectifying circuit rectifies alternating current voltage into direct current voltage to be output, the first diode prevents load current from flowing back, the energy storage capacitor is used for storing electric energy and supplying power to a load, and a one-way conduction circuit, a switching circuit and a detection device are arranged in each peak value detection module; the detection device of each peak detection module can be connected in parallel with the inductor through the switching circuit of the detection device; the piezoelectric transducer has the advantages that only the positive half-cycle peak value of the output voltage of the piezoelectric transducer needs to be detected, the number of components needed by the peak value detection module is small, the overall circuit size is reduced, the cost is reduced, inductors can be shared at the same time during expansion, a time division multiplexing mode does not need to be adopted, and the expansion performance is high.
Owner:NINGBO UNIV