Top PDF Apparatus and method for driving an ultrasonic transducer

Apparatus and method for driving an ultrasonic transducer

Apparatus and method for driving an ultrasonic transducer

A method and apparatus for electronically driving an ultrasonic acoustic transducer. The transducer is operable in two modes; in a first mode, the lock-in frequency of the transducer is determined; in a second mode, the lock-in frequency determined in the first mode is used to modulate a tone-burst pulse to drive the transducer in an efficient manner. Operating in the first mode, the lock-in frequency is determined by exciting the transducer with a series of tone bursts, where each tone burst comprises an electronic pulse modulated by a tone of one frequency selected from a range of frequencies, and measuring the response of the transducer to each tone burst. In an alternative embodiment, the excitation of the transducer in the first mode is provided by a signal whose frequency is swept over a range. The response of the transducer is sampled at various times during the sweep. The lock-in frequency is chosen by examining the responses and choosing the frequency which gives the best response. Operating in the second mode, the transducer is driven with an electronic tone burst generated by modulating said an electronic pulse with a tone of the determined lock-in frequency.
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Noncontact Driving System Using Induction Based Method and Integrated Piezoelectric Ultrasonic Transducers

Noncontact Driving System Using Induction Based Method and Integrated Piezoelectric Ultrasonic Transducers

Integrated Ultrasonic Transducers (IUTs) have been developed for high-temperature nondestructive evaluation applica- tions. In many field, it would be helpful if a pipe covered by a protective layer of about 10 cm thickness, which is under operation at several hundred Celsius, could be inspected from above the protective layer by an IUT. As a first step to- ward achieving the inspection of such a pipeline, an induction-based method using coils is presented together with IUTs. This study focuses on the effects of the separation distance (liftoff) between the coils on the ultrasonic signal strength and bandwidth of the IUTs. Ultrasonic signals were generated and received by the IUTs on a steel plate with a sufficient strength for thickness measurements when the liftoff was 20 cm. It was also shown that a ferrite disc together with the coils enhanced the received signal strength even when the liftoff was over 10 cm.
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An Approach to Designing a Dual Frequency Piezoelectric Ultrasonic Transducer

An Approach to Designing a Dual Frequency Piezoelectric Ultrasonic Transducer

destroyed and the difference between the nodes and antinodes is decreased. Therefore the cleaning quality can be improved. In recent decades, there has been some interest in designing dual frequency piezoelectric transducer by means of two groups of piezoelectric ce- ramic elements. One group is used as the active ele- ment which is connected to an electrical generator; the other group is used as the controlling elements which are connected to inductance or capacitance. When the inductance or capacitance is changed, the resonance frequency can be adjusted by means of the piezoelec- tric effect [6-8]. Lin and Xu [9] presented the analysis of a sandwich transducer with two sets of piezoelectric ce- ramic elements which are separated by a middle metal cone. The two sets of piezoelectric elements are excited separately, and therefore two groups of resonance and anti-resonance frequency can be obtained. Lin [10] also studied an improved cymbal transducer that consists of a combined piezoelectric ring and metal ring, and metal caps. In another paper, Lin et al. [11] studied a composite transducer that consists of a sandwich lon- gitudinal piezoelectric transducer, an isotropic metal hollow cylinder with large radial dimension, and the front and back metal radiation mass. In their paper, the resonance frequency was found analytically by elec- trical equivalent circuit model method. Finally, they manufactured some transducers and measured the res- onance frequency and the radiation acoustic field in order to compare them with the analytical and numer- ical results. Deniz [12] studied numerical and experi- mental design of a multi-frequency underwater acous- tic transducer with two sets of piezoelectric tubes. In this study, one of the tubes operated at about 30kHz and the other one at about 60kHz. Asami and Miura [13] investigated a new type of ultrasound longitudinal- torsional vibration source consisting of a longitudinal transducer and a torsional transducer at opposite ends of a uniform rod as a vibration source. The individ- ual vibrations could be controlled. The longitudinal vibration distributions for driving only the longitudi- nal transducer and the torsional vibration distributions for driving only the torsional transducer were similar in the uniform rod.
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A pipe organ-inspired ultrasonic transducer

A pipe organ-inspired ultrasonic transducer

The mathematical model used in this article is a transmission line (1D in space) model introduced by Walker & Mulholland (2010) and discussed further by Walker & Mulholland (2016). The model outputs the transmission voltage response (TVR) and the reception force response (RFR) of the ultrasonic transducer, from which the bandwidths are calculated and compared against the standard transducer de- sign. As mentioned, standard electrostatic transducers operate by electrically ex- citing a stretch mylar membrane over a conducting backplate. The novel design considered in this approach uses acoustic amplifying conduits emanating from an air-filled cavity in the backplate. A simplified exploded sketch of the design is shown in Figure 2.
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The Experiment of Acoustic Levitation and the Analysis by Simulation

The Experiment of Acoustic Levitation and the Analysis by Simulation

Acoustic levitation technology is mainly used to simulate various effects in the space environment, and better solve people’s increasingly high demands on the experimental environment. Although the space resources that people have ob- tained so far are still very limited, the ultrasonic levitation technology is a good direction to create a vacuum environment similar to gravity-free, can also solve many chemical pharmaceuticals, no container processing, liquid solidification, precision instrument processing and other aspects. Regarding suspension, people may hear the most maglev train. In fact, the physical methods for achieving ob- ject suspension are various, such as: pneumatic suspension, electromagnetic sus- How to cite this paper: Zhang, F.Q. and
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3D Reconstruction of Surface Topography using Ultrasonic Transducer

3D Reconstruction of Surface Topography using Ultrasonic Transducer

The above diagram shows a schematic diagram of the scanning equipment setup. It includes the wrench that was used as a target. A focusing transducer was immersed within the water bath and positioned so the wave was focused on the wrench surface. The transducer was connected to an x-y positioning stage, so it may well be scanned across the assigned region. The dimensions and the resolution of the scan were selected according to the surface geometry and the degree of accuracy required.

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Ultrasonic Park Controller

Ultrasonic Park Controller

Ultrasonic transducers have many critical specifications. Transmitting frequency is the usable frequency range of the device. Bandwidth is the difference between low and high operational frequency limits. Rated signal power available from transducer is another important specification. Transmit sensitivity is the ratio of sound pressure produced to input voltage. Receive

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Ultrasonic transducer attenuation behavior 
		of fiber glass composite laminates (FGCL) through signal filtering 
		approach

Ultrasonic transducer attenuation behavior of fiber glass composite laminates (FGCL) through signal filtering approach

generated high voltage electrical pulse and then drive the transducer to generate high frequency ultrasonic energy. This ultrasonic energy finally propagates through the specimen in the form of wave signal. If the discontinuity occurs along the wave path, part of ultrasonic energy will reflect back from the flaw surface. Consequently, the reflected signal from flaw surface as known as echo will transform back into an electrical signal that finally is displayed on a screen. During this investigation, there are 9 sets of ultrasonic testing data was recorded based on type of defect and location along the wave path. An averaging of SNR calculation will be performed based on several testing data are performed in next research step.
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Non-Intrusive Liquid Level Detection System

Non-Intrusive Liquid Level Detection System

Most continuous monitoring systems use a transducer unit to interact with the liquid level being measured. Ultrasonic devices emit electromagnetic energy in order to detect the level of the liquid at that second. A non-contact device, such as Ultrasonic, does not require direct contact with the liquid surface in order to perform properly.

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Direct sequence spread spectrum ultrasonic testing device

Direct sequence spread spectrum ultrasonic testing device

Techniques for providing an ultrasonic flaw detection system are disclosed. A continuous wave of wide-band direct-sequence spread-spectrum signals continuously drives one or more transmitting transducers, thereby flooding a test object with coded ultrasound. In operation, the ultrasonic testing system is capable of reliably and predictably transmitting a high degree of ultrasonic energy (power) to a test object. Code division multiplexing correlation techniques using a variably delayed replica of a selected segment of the DSSS signal are applied to the signals received by the receiving transducers to generate a signature representing the signal returned from all reflectors within the test object.
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Focusing system for an ultrasonic transducer

Focusing system for an ultrasonic transducer

hemisphere piezoelectric crystal having a non-uniform beam width and a better lateral resolution than the plane transducer due to reduced beam width in the foc... Objective of Research T[r]

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A squeegee coating apparatus for producing a liquid crystal based bio transducer

A squeegee coating apparatus for producing a liquid crystal based bio transducer

The apparatus for producing LC substrates comprising a platform having a petri dish and a stepper motor attached to the horizontal linear slider for moving the dish from a loading region[r]

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Parallel Receiving Needle Beam Ultrasonic Testing Technique

Parallel Receiving Needle Beam Ultrasonic Testing Technique

Figure 10 shows the summary of the parallel receiving needle beam ultrasonic technique, that is, a method for simultaneously inspecting a cross section of a test object using a transducer array. The receiving needle beam means a continuous line of receiving beam focal points. The tech- nique involves transmitting ultrasonic waves from all the ultrasonic transducer elements in the array, receiving reflected waves generated by the transmitted ultrasonic waves using all the ultrasonic transducer elements in the array, converting the received signals into digital waveform signals, converting the time axis of the digitalized received signal of each element, and additively synthesizing the time-axis-converted received signals of each element. The continuous line of receiving beam focal points formed inside the test object essentially means fixing the receiving beam Received signal i
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Optimization Design of Phased Array Ultrasonic Transducer Arrays

Optimization Design of Phased Array Ultrasonic Transducer Arrays

In the current study, an array of uniform two-dimensional layout is the most widely used form of an array of ultrasonic transducers [4] . As shown in FIG. 1 and FIG. 2, the array is located on the xoy plane. N transducer elements along the x-axis and M transducer elements along the y-axis are uniformly arranged at a pitch of r x and r y , respectively, for a total of N × M elements.

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A theoretical model of an ultrasonic transducer incorporating spherical resonators

A theoretical model of an ultrasonic transducer incorporating spherical resonators

[Received on 6 September 2013; revised on 16 December 2014; accepted on 18 July 2015] This article considers the theoretical modelling of a novel electrostatic transducer in which the back- plate consists of many spherical resonators. Three analytical models are considered, each of which pro- duce impedance profiles of the device, in addition to transmission voltage responses and reception force responses, all of which closely agree. Design parameters are then varied to investigate their influence on the resonant frequencies and other model outputs.

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High frequency ultrasonic assisted mass transfer for water batch reactor

High frequency ultrasonic assisted mass transfer for water batch reactor

varied with the ultrasonic frequency (Yasuda et al ., 2011). Therefore, higher frequency generates smaller droplet and thus increasing the surface area for the mass transfer process (Avvaru et al., 2006). To date, most of the current studies are performed under low frequency ultrasonic waves (20 kHz) for the desorption purpose (Gantert and Moller, 2012; Tanaka et al. , 2014). Hence, the present study focuses on the effect of high frequency ultrasonic waves of 1.7 MHz in mass transfer process. A custom- made ultrasonic system was designed prior to the gas- liquid mass transfer study for CO 2 desorption. The power
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Piezoceramic Element Design and Fabrication for Ultrasonic Transducer of Gas Meter

Piezoceramic Element Design and Fabrication for Ultrasonic Transducer of Gas Meter

It is a common practice to analyze the vibration characteristics of the piezoelectric disk through one-dimensional analytic models. These one-dimensional models assume that the piezoelectric disk vibrates in thickness extensional mode and behaves like the motion of a piston. They are applicable to a piezo disk with diameter to thickness (d/h) ratios greater than or around 20. This is due to the fact that under such geometrical constraint, the vibration characteristic related to the thickness extensional mode becomes dominant. However, many designers employ the disc with the d/h ratios much less than 20 due to the space limitations in their design. In these cases, the use of the finite element method to analyze the vibration characteristics of a piezoelectric disc becomes indispensable. It implies that the one- dimensional models are no longer adequate to completely analyze the performance of an ultrasonic transducer. It is, therefore, necessary to analyze the piezoelectric transducer using a complete three-dimensional model.
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A Low Intensity Ultrasound Neural Modulation System for Brain Stimulation

A Low Intensity Ultrasound Neural Modulation System for Brain Stimulation

The structure of the ultrasound system is shown in Figure 1. It can be seen from Figure 1 that the overall system consists of arc phased array transducer and electronic system. The frequency of the electronic system varies from several hundred thousand o f hertz to several megahertz. The final output power can reach

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Acoustic and video imaging system for quality determination of pharmaceutical products

Acoustic and video imaging system for quality determination of pharmaceutical products

A flexible system for determining the quality of pharmaceutical products based on characteristics such as, for example, mass, shape, hardness, size, color and surface texture is disclosed herein. The quality determination apparatus includes a feeder assembly for sequentially dropping individual product samples upon an impact transducer arrangement. The impact transducer generates transducer signals indicative of the physical characteristics of each product sample. In addition, an imaging device operates to synthesize a digital image representation of each product sample. The transducer signal and digital image representation corresponding to each product are analyzed so as to determine the appropriate degree of quality to be associated therewith.
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Method and means for gravity table automation

Method and means for gravity table automation

An apparatus for determining quality of a pharma ceutical product of a prede?ned type, comprising: impact transducer means for generating a transducer signal indicative of a set of physi[r]

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