94 results about "Acoustic levitation" patented technology

A gas sensor for sensing the presence of a gas includes an IR source, a microphone, a reference gas substantially similar to the gas to be detected, a reference body defining a reference chamber therein, the reference chamber having a pressure port coupled to the microphone, and a broad-band optical window through which at least IR wavelengths corresponding to absorption peaks of the predetermined gas may pass. The window is disposed between the IR source and reference chamber. The reference gas is contained within the reference chamber between the optical window and the microphone. The sensor can be included in a hand-held gas detection instrument having power supply, an outer shell, a circuit board assembly including sensor circuitry, a suction pump, actuation controls and status indicators. A probe defining a lumen therethrough supplies the sample gas.

An acoustic detection of a discrete acoustic signal allows to detect a leak behind a casing (23) of a borehole. An acoustic amplitude (AA) is sampled during a recording time period (24; 64) at a determined position along the tube. Time intervals (26; 66) are defined inside of the recording time period (24), and for each time interval (26) the measured acoustic amplitudes are processed to obtain respectively a corresponding power-frequency spectrum (261). A plurality of the power-frequency spectra are analyzed to identify the discrete acoustic signal by detecting time and frequency dependant changes of power. Preferably the processing involves a Fourier transform analysis. A power-frequency time plot is used to conveniently identify the discrete acoustic event.

A method and system for examining tissue are provided in which the tissue is maintained in a position so that it may be insonified with a plurality of pulsed spherical or cylindrical acoustic waves. The insonifying acoustic waves are scattered by the tissue so that scattered acoustic radiation including a mix of reflected and transmitted acoustic waves is received. A representation of a portion of the tissue is then derived from the received scattered acoustic radiation.

Various techniques for driving phased array systems are described, specifically intended for acoustic phased arrays with applications to mid-air haptics, parametric audio, acoustic levitation and acoustic imaging, including a system: 1) that is capable of mitigating the effect of the changes in the air to provide a consistent haptic experience; 2) that produces trap points in air; 3) that defines phased-array optimization in terms of vectors for the production of more consistent haptic effects; 4) that defines one or more control points or regions in space via a controlled acoustic field; 5) that uses a reduced representation method for the construction of acoustic basis functions; 6) that performs efficient evaluation of complex-valued functions for a large quantity of throughput; 7) that generates a Krylov sub-space of a matrix; and 8) that maximizes an objective described by different control points and / or regions to those used to create the acoustic basis functions.

The invention discloses an automobile interior acoustic field prediction method based on a partition-of-unity finite element-meshless cell. The method comprises the steps of utilizing an automobile interior air acoustic cavity mesh model, defining the cell node support region of the automobile interior air acoustic cavity mesh model by use of the relation of a layer of connected nodes, constructing a local approximation function by use of a radial point interpolation method within the node support region of the automobile interior air acoustic cavity mesh model, and meanwhile, performing approximation by use of an isoparametric element shape function within the global mesh range of the automobile interior acoustic cavity, constructing a shape function and the gradient thereof at a Gauss integral point of the automobile interior acoustic cavity model in an isoparametric element integration manner, constructing the Galerkin weak-form of an acoustic equation of automobile interior acoustic cavity problems to obtain the system equation of the automobile interior acoustic cavity mesh model, thereby predicting the modal frequency and the mode of vibration of the automobile interior acoustic cavity, and meanwhile, predicting the acoustic response of the automobile interior acoustic cavity under the excitation of an engine and assessing the calculation results. The automobile interior acoustic field prediction method based on the partition-of-unity finite element-meshless cell is capable of obtaining better calculation results than a finite element method in the automobile interior acoustic cavity vibration noise prediction problem.

A medical ultrasound device is disclosed. The device comprises an elongated body having a proximal end and a distal end region (1). One or more ultrasound transducers (4) for generating acoustic radiation are positioned in the distal end region, inside the elongated body. A transmission element (5) which is substantially transparent to acoustic radiation is positioned in the radiation path of the acoustic radiation, and a controller unit is operatively connected to the ultrasound transducer. The transmission element and the one or more ultrasound transducers are mounted so that an acoustic path length (8) between the transmission element (5) and the ultrasound transducer (4) varies with contact force (10) imposed to the distal end region. The controller unit detects the acoustic path length between the ultrasound transducer and the transmission element and determines the contact force from the detected acoustic path length. In an embodiment, the medical device is an ultrasound RF ablation catheter.

The invention discloses an acoustic levitation polishing machine of mechanically representing nano test samples and comprises a machine frame, a pulse power source, a holding fixture that is used for clamping a working piece to be processed, an ultrasonic energy transducer, a container that is used for storing polishing liquid, an ultrasonic reflecting end, and a tuning mechanism that is used for adjusting the distance between the ultrasonic reflecting end and the ultrasonic energy transducer. The ultrasonic energy transducer, the container and the tuning mechanism are all arranged above the machine frame, the pulse power source is connected with the ultrasonic energy transducer, the container is arranged under the ultrasonic energy transducer, the holding fixture is arranged above the container and is connected with a belt wheel actuating mechanism, and the ultrasonic reflecting end is arranged under the container, coordinated with the ultrasonic energy transducer and connected with the tuning mechanism. The invention provides an acoustic levitation polishing machine of the mechanically representing nano test samples with good applicability and well polishing effect.

Various techniques for driving phased array systems are described, specifically intended for acoustic phased arrays with applications to mid-air haptics, parametric audio, acoustic levitation and acoustic imaging, including a system: 1) that is capable of mitigating the effect of the changes in the air to provide a consistent haptic experience; 2) that produces trap points in air; 3) that defines phased-array optimization in terms of vectors for the production of more consistent haptic effects; 4) that defines one or more control points or regions in space via a controlled acoustic field; 5) that uses a reduced representation method for the construction of acoustic basis functions; 6) that performs efficient evaluation of complex-valued functions for a large quantity of throughput; 7) that generates a Krylov sub-space of a matrix; and 8) that maximizes an objective described by different control points and / or regions to those used to create the acoustic basis functions.

The invention relates to an acoustic interaction active noise reduction device arranged at a vent pipe port. The acoustic interaction active noise reduction device comprises a shell, a loudspeaker, areference microphone, a plurality of error microphones, a controller and a flow diffuser. The loudspeaker is arranged in the shell. The reference microphone is arranged on the top of the shell. The acoustic input end of the reference microphone faces the outer portion of the shell. The error microphones are arranged on the bottom surface of the shell and are arranged in the positions close to theedge of the bottom surface. The controller is arranged in the shell. The loudspeaker, the reference microphone and the error microphones are all in lead wire connection with the controller. A third through hole is formed in the center of the flow diffuser. The bottom surface of the shell is arranged in the third through hole. The invention further provides an acoustic interaction active noise reduction control method. The acoustic interaction active noise reduction device is simple in structure and small in size, and acoustic interaction can be achieved through the active noise reduction device during active noise reduction.

The invention provides a method for acoustic detection of the condition of the road and the tyre. The invention relates to a method for determining the condition of a road and the condition of a tyre, including the steps of: recording a measurement of the sound signal produced by the tyre traveling on the road during a given time interval; determining the spectral power density of the sound signal over a given frequency interval; segmenting the frequency interval into a plurality of frequency bands; and associating with each frequency band a piece of data representing the mean sound power measured in said frequency band, the representative data from a measurement forming the variables of a vector associated with said measurement; determining a condition of the road and of the tyre by means of a discriminant analysis of the data supported by a knowledge base. The representative data forming the variables of the vector associated with a measurement are obtained by calculating the ratio between the mean sound power measured in one frequency band and the total sound power measured over the entire frequency interval.

Systems and method for acoustic detection using flow sensors are provided. One system includes a flow conduit configured to allow fluid flow therethrough and a flow disrupter configured to impart a flow disturbance to the fluid flow. The system also includes at least one of a first sensor or a second sensor. The first sensor is disposed within the flow conduit at a first position, wherein the first sensor is responsive to first disturbances and configured to generate signals characteristic of the first disturbances. The second sensor is disposed within the flow conduit at a second position, wherein the second sensor is responsive to second disturbances and configured to generate signals characteristic of the second disturbances. The system additionally includes a processor operably coupled to the first and second sensors, wherein the processor is configured to distinguish between signals characteristic of the first and second disturbances.

Methods, systems, and computer readable media for acoustic detection of activated phase-change contrast agents are disclosed. According to one aspect, a method for acoustic detection of activated ultrasound phase-change contrast agents includes initiating a phase transition in a phase change contrast agent causing a change of the diameter of the activated phase change contrast agent, and detecting an acoustic signature of the change of diameter of the activated phase change contrast agent.

The invention discloses an acoustic levitation multi-droplet evaporation and combustion experiment device and method and relates to the technical field of internal combustion engine combustion detection. The device comprises an acoustic levitation device, an evaporation combustion chamber (1), an acoustic levitation control system and a control unit (2), wherein the evaporation combustion chamber (1) is connected with the acoustic levitation device, and the control unit (2) is connected with the evaporation combustion chamber (1) through a wire; the acoustic levitation device comprises a frequency converter (7) and a reflector (13); the acoustic levitation control system comprises a signal generator (8), a power amplifier (10) and a power meter (12). By the device, the experimental researches of the evaporation and combustion features of multiple tiny droplets under a deformation-free condition can be achieved.

The invention provides a multiple physical environment controllable acoustic levitation experiment apparatus. A support base seat and a transparent pressure resistance cover are connected to form an enclosed cavity; an electric elevating platform is mounted on the support base seat, a sound reflecting end on the electric elevating platform is driven via an electric motor to move up and down, an energy transducer is fixed on the support base seat via support rods, and a supersonic generator is connected with the energy transducer; that one of a step-shaped amplitude transforming rod, a conicalamplitude transforming rod and an exponential type amplitude transforming rod shares the same axis with an output end of the energy transducer can be guaranteed via a lower end of the energy transducer via movement of a converter; a sound emitting end of the amplitude transforming rod is right opposite to the sound reflecting end; a humidifier, a heating pipe, an air pressure gauge, a temperaturesensor and a humidity sensor are mounted in the cavity; the cavity is also provided with a vent hole communicated with the outside or a gas transmission device. Via the multiple physical environment controllable acoustic levitation experiment apparatus, requirements for different physical experiments can be met, and different types of amplitude transforming rods can be chosen at will according todifferent samples to be levitated.

The invention discloses a digitization method for a railway vehicle bearing acoustic detection system and an implementation device for the digitization method, and belongs to the technical field of train security monitoring. A master control system, a data collection system, a wheel sensor, a startup sensor, a digital microphone array and a network device are arranged in a rail edge protection cabinet for processing train signals, obtaining vehicle passing data and uploading the data to a vehicle depot data center through a high-speed network in forms of specific messages. By means of the digitization method and the implementation device, vehicle bearing sounds are collected directly through digital microphones, the vehicle bearing sounds and other signals are directly processed in the rail edge protection cabinet, all field data are digitized, signal noise caused when analog signals are transmitted in a long-line manner is avoided, the signal quality is high, and the anti-interference capacity is high; the digitization data are directly transmitted to a central server through a high-speed network channel, and cable line resources are saved.

The invention relates to a disc micro-engine gyroscope based on the sound suspension in the field of micro motor technique. The invention comprises: eight capacitance plates, a partition electrode, a electricity plate, a base plate, a insulating layer, four bracing columns and a micro rotors, wherein the base plate and the partition electrode are positioned on two sides of the electricity plate along with the sickness direction; the insulating layer is positioned on the base plate; the eight capacitance plates are positioned on the insulating layer evenly, which forms four bracing columns on the insulating layer; the micro rotor is positioned on the four bracing columns.

The invention discloses an acoustic detection and blind signal separation-based air tightness monitoring method and apparatus. The objective of the invention is to solve the problems of inconvenient wire leading due to high air pressure, incapability of positioning gas leakage positions and incapability of identifying multiple-point gas leakage in the application of air tightness monitoring and detection of equipment of compressors and gas tanks. According to the acoustic detection and blind signal separation-based air tightness monitoring method of the invention, a plurality of high-sensitivity acoustic sensors are bonded at different positions of a detected container through utilizing a turbulent flow sounding effect in a gas leakage process; acoustic signals are conditioned and amplified; after being acquired by a microprocessor, the conditioned and amplified acoustic signals are subjected to blind signal separation processing; recognition of multiple-point gas leakage and gas leakage position positioning are performed through waveform comparison and signal intensity comparison; light flashing and tweeting are adopted to perform warning; and signal waveforms, gas leakage positions and the number of gas leakage points are displayed on an LCD screen. The acoustic detection and blind signal separation-based air tightness monitoring method and apparatus of the invention can be used for long-term gas leakage online monitoring of equipment such as pipelines and containers, and can be also used for air tightness quality detection of products. The acoustic detection and blind signal separation-based air tightness monitoring method and apparatus have the advantages of high accuracy, convenient operation and low price.

An ultrasonic clutch includes a driving element, a driven element and at least one alternating current (AC) power source. The driving element and the driven element are connected to a shaft of a driving device and an output axle of a loading, respectively. At least one of the driving element and the driven element is a piezoelectric device. When at least one of the driving element and the driven element is electrically connected to an AC power source, the near-field acoustic levitation, generated from the flexural vibration of the piezoelectric resonator above the piezoelectric resonator, occurs to push the driven element away from the driving element. Thus, the output shaft of the loading does not rotate with the axle of the driving device.

The application discloses a detection method and system for shear-wave velocity of acoustic radiation. The detection method comprises following steps: respectively selecting an impact position, a first detection position and a second detection position and impacting acoustic radiation force of the impact position; respectively accumulating two groups of time-depth-shear wave displacement matrixes along the depth direction in order to obtain two groups of accumulative displacement arrays formed by accumulation and composition; respectively searching maximum value of the two groups of accumulative displacement arrays and utilizing maximum value as shear-wave crest position time; and calculating shear-wave velocity according to the distance between the first detection position and the second detection position and shear-wave crest position time of the first detection position and the second detection position. The detection method and system for shear-wave velocity of acoustic radiation have following beneficial effects: without searching for focal positions of the displacement matrixes, the displacement matrixes are firstly accumulated along the depth direction and information on shear-wave crest in different depths is comprehensively utilized so that the time position where most shear-wave crests pass through is found out and the horizontal position where the maximum value is located is obtained, therefore calculating shear-wave velocity.

The invention relates to a device and a method for the acoustic examination of objects (20, 30, 40) in the environment of a means of conveyance (10). The method comprises the steps of: - detecting sound emitted by an object (20, 30, 40) in the environment by means of a sensor (1, 2, 3, 4), - evaluating the sensor signal over time, and - recognising a position and / or a relative movement (P) and / or a spatial extent of the object (20, 30, 40) in the environment on the basis of a comparison of a time profile (5) of an intensity variable of the sensor signal with a predefined reference (6).

The invention discloses an acoustic levitation system based on an ultrasonic array and a control method of the acoustic levitation system. The acoustic levitation system comprises an upper computer, acontroller, FPGA modules, a driving circuit and a single-sided ultrasonic sensor array. An object is levitated up by calculating a phase of the ultrasonic array and generating a specific sound fieldabove the single-sided ultrasonic sensor array. Compared with the conventional ultrasonic standing wave levitation, the defects of the ultrasonic standing wave levitation at present are overcome; reflection components are not needed; hardware equipment of acoustic levitation is greatly simplified; the levitated object does not need to be surrounded by acoustic components; the object can be levitated in an open space; the maneuverability is also greatly improved; the sound field formed by the array type levitation is capable of easily completing movement along a specific trajectory, so that theconfinement of standing wave nodes is avoided; the application scenes of an acoustic levitation technology are extended; in addition, the acoustic levitation system is simple in overall structure andeasy to implement, is suitable for being extensively popularized and applied, and is especially applicable to processing and transportation of non-contact type materials and biological experiments, and the like.

The acoustic leak detection system with environmental noise isolation provides for the acoustic detection of leaks in a pipe while minimizing interference from external or environmental noise. The acoustic leak detection system includes a hollow shell adapted for positioning about the pipe to be inspected. A pair of gaskets are circumferentially secured to the inner surface of the hollow shell so that the pair of gaskets bear against the outer surface of the pipe to form an acoustically isolated region defined between the pipe, the pair of gaskets and the inner surface of the hollow shell. An acoustic sensor, microphone or the like is mounted on the hollow shell within the acoustically isolated region for detecting any acoustic signals; i.e., the sound produced by a leak in the pipe within the acoustically isolated region. Upon detection of a leak, an alert signal is generated.

The invention relates to the technical field of nanometer particle preparation, in particular to a gold nanometer particle and a method for preparing the gold nanometer particle with acoustic levitation. The method for preparing the gold nanometer particle with the acoustic suspension comprises the following steps that (1) acoustic suspension is conducted on a mixed solution of HAuCl4.3H2O and polyvinylpyrrolidone, so that suspension liquid is obtained; and (2) under the acoustic suspension conditions in the step (1), a NaBH4 solution is added into the suspension liquid for a reduction reaction, and then suspending gold nanometer particles are obtained, wherein during acoustic suspension, the ultrasonic power of an acoustic suspension instrument is 250-450 W, the ultrasonic frequency is 20-22 KHz, and the distance between the reflection end and the transmitting end is 35-50 mm. Under the specific acoustic suspension conditions, the NaBH4 solution is adopted to conduct reduction on a HAuCl4.3H2O solution, the prepared gold nanometer particles are remarkably higher in catalytic performance than the gold nanometer particles prepared by the adoption of a conventional method.

An apparatus and method thereof includes at least one acoustic transducer for receiving acoustic emissions produced during a semiconductor fabrication process. The acoustic transducer is mounted to various mechanical components of a semiconductor processing equipment in a manner so that the acoustic transducer receives acoustic emissions produced during the fabrication process. The received acoustic emissions are analyzed in in-situ to identify and determine surface characteristics of the wafer.

The invention relates to the technical field of nanoparticle preparation, in particular to a method for preparing ruthenium nanoparticles without a container. The method comprises the following stepsof (1) performing acoustic suspension on a mixed solution of RuCl3.3H2O and polyvinylpyrrolidone to obtain a suspension; and (2) under the acoustic suspension condition of the step (1), adding a NaBH4solution into the suspension, and carrying out a reduction reaction to obtain suspended ruthenium nanoparticles, wherein during the acoustic suspension, the ultrasonic power of an acoustic suspensioninstrument is 250 to 450W, the ultrasonic frequency is 20 to 22KHz, and the distance between a reflecting end and an emitting end is 15 to 30mm. According to the method, the ruthenium nanoparticles are prepared by reducing the RuCl3.3H2O solution with the NaBH4 solution in a stable suspension state in a container-free environment provided by an acoustic suspension technology, so that the preparation process is simple, and the prepared ruthenium nanoparticles are relatively small in particle size and narrow in particle size distribution.

The invention is applicable to the technical field of measurement, and provides an acoustic detection device, system and method, computer equipment and a storage medium. The acoustic detection devicecomprises a sound source, and an acoustic field detector arranged in front of the output end of the sound source; the acoustic field detector comprises at least one multi-directional acoustic field detection component, each multi-directional acoustic field detection component comprises multiple laser detection devices; the multiple laser detection devices are arranged in a preset manner, so that detection light beams corresponding to the multiple laser detection devices can be interweaved to form a two-dimensional meshy cross section on a detection plane in front of the output end of the soundsource, and the laser detection devices are arranged in such the arrangement manner to detect the acoustic field on the two-dimensional meshy cross section. According to the device, system and methodprovided by the invention, the acoustic field to be detected can be continuously sampled, via simultaneous measurement in multiple directions, the continuous and multi-dimensional measured data can be provided for a subsequent process for computing the shape of a detection target, and thus the finally measured shape of the detection target has the relatively high resolution.

The present invention provides a method and device for the acoustic ejection of fluid droplets having a constant drop size from fluid-containing reservoirs having varying fluid heights contained therein without the need for repositioning the acoustic ejector in the z direction by adjusting the RF frequency and amplitude. In one embodiment, the device is comprised of: a plurality of reservoirs each adapted to contain a fluid; an ejector comprising a means for generating acoustic radiation, means for controlling the RF frequency and amplitude used to generate the acoustic radiation, means for focusing the acoustic radiation at a focal point near the fluid surface in each of the reservoirs; and a means for positioning the ejector in acoustically coupled relationship to each of the reservoirs. The invention is useful in a number of contexts, particularly in the preparation of biomolecular arrays.

The invention discloses a multi-sound field interfered acoustic levitation device and a sound filed switching method. The device comprises a microcontroller, a driving motor module, a power module, acontroller, an upper shell, a lower shell, a connection part and a plurality of ultrasonic wave emission areas. The upper shell and the lower shell are opposite and are set in parallel. The upper shell and the lower shell are connected by the connection part. The upper shell and the lower shell are spaced to form a levitation space. The plurality of ultrasonic wave emission areas are set on the upper shell and the lower shell and are distributed according to an array. Each ultrasonic wave emission area comprises a plurality of ultrasonic wave emitters. The controller outputs a signal to the microcontroller. The microcontroller receives the signal and outputs a square wave signal to the driving motor module. The driving motor module drives the plurality of ultrasonic wave emission areas towork. An initial phase of each ultrasonic wave emission area is further adjusted through change of the signal output by the controller, and curl of a sound field is adjusted.

An acoustic detection system for detecting at least partly submerged targets in a sensitive area defined with respect to an infrastructure, wherein the system includes at least one multistatic detection group, each multistatic detection group defining a detection area, and comprising: a submerged transmitter transmitting at low frequencies; a plurality of submerged receivers comprising at least two receivers, each receiver of a given group forming, with the transmitter of the group, a bistatic pair, each bistatic pair generating an elementary detection area surrounding a blind zone, the detection area of the group being formed by all of the elementary detection areas of the receivers of the group, the blind zone of each receiver in a given detection group being at least partly covered by the elementary detection areas of the neighbouring receivers of the detection system.

The invention provides an acoustic levitation device in a liquid environment. The acoustic levitation device comprises a waveguide circular tube, a hydrophone, a transducer used for transmitting acoustic waves, a signal generator and an oscilloscope; the waveguide circular tube is in a shape of a cylindrical bucket with an opening in one end, the opening is sealed through a steel plate, and the waveguide circular tube is filled with a liquid medium; the transducer is arranged at the bottom of the waveguide circular tube, the piston type transducer is adopted and is connected with the signal generator outside the waveguide circular tube, and the hydrophone is suspended in the liquid medium and is connected with the oscilloscope outside the waveguide circular tube. An acoustic levitation method comprises the following steps that (1) a sound field in air is established; (2) a sound field in the liquid environment is calculated; (3) a weight threshold is measured; (4) according to an existing frequency, the corresponding waveguide circular tube is designed and organic glass is adopted as the side wall, the bottom end of the waveguide circular tube is provided with the transducer, the top end of the waveguide circular tube adopts a round face rigid reflection end made from steel, the height of an intermediate medium, such as water, reaches the optimum size of the waveguide circulartube through simulation calculation.