In this work we use a 3D quantitative CT imaging ultrasound system to characterise polymer gel dosimeters. The system comprises of two identical 5 MHz 128 element phasedarray ultrasound transducers co-axially aligned and submerged in water as a coupling agent. Rotational and translational movement of the gel dosimeter sample between the transducers were performed using a robotic arm. Ultrasound...

The time reversal mirror (TRM) is a method which can be effective in NDE of defects in materials. In this case an input ultrasonic wave is transmitted into the examined sample, then recorded by receiving transducers, time reversed and sent back by the same transducers. A simple numerical model of a solid plate with a crack was developed. The propagation of ultrasonic waves used in time reversal...

Ultrasonic testing systems have been extensively used in medical imaging and non-destructive testing applications. Generally, these systems aim at a particular application or target material. To make these systems portable and more adaptable to the test environments, this study presents a reconfigurable ultrasonic testing system (RUTS), which possesses dynamic reconfiguration capabilities. RUTS...

A layer-by-layer deposition method for producing dual-layer ultrasonic transducers from piezoelectric copolymers has been developed. The method uses a combination of customized and standard processing to obtain 2D array transducers with electrical connection of the individual elements routed directly to the rear of the substrate. A numerical model was implemented to study basic parameters effec...

Application of ultrasonic methods to structural health monitoring requires a compromise between coverage and complexity, making it desirable to use as few transducers as possible to cover the largest area. Such a consideration leads to the use of very sparse arrays where transducers are spatially distributed over a large area and are permanently attached to the structure. For plate-like geometr...

Transducers based on piezoelectric crystals dominate the biomedical ultrasonic imaging field. However, fabrication difficulties for piezoelectric transducers limit their usage for complex imaging modalities such as 2D imaging, high frequency imaging, and forward looking intravascular imaging. Capacitive micromachined ultrasonic transducers (CMUTs) have been proposed to overcome these limitation...

A number of tomographic and phased-array methods have been proposed for generating two dimensional images of plate-like structures using sparse arrays of spatially distributed ultrasonic transducers. The phased array differential approach is considered here whereby pulse echo and through transmission signals are recorded before and after localized damaged is introduced, and differenced signals ...

In this paper, an improved method for the measurement of acoustic power and electro-acoustic efficiency of high power ultrasonic transducers is presented. The measuring principle is described, the experimental results are given. In comparison with traditional methods, the method presented in this paper has the advantages of simplicity, economy and practicality. The most important is that it can...

Non-destructive Hertzian contacts are used to couple ultrasonic waves for characterization and defect detection in anisotropic solid pates. Spring loaded quartz rods bonded to PZT-5H transducers are used to form a point source point receiver pair and ultrasonic plate modes are excited and detected around 200 KHz with 50 dB signal to ratio at the receiving end. Measurements are performed on sili...