Diagnostic ultrasound has been widely used in clinical applications, such as soft tissue abnormality detection and blood flow detection. However, due to the complexity of ultrasonic wave propagation and scattering in biological tissues which generally involves wave reflection, refraction, scattering, absorption and other wave phenomena, it has always been a rather difficult task to interpret th...

In this study a novel servo speed control system for travelling-wave ultrasonic motor (TWUSM) has been presented. A drive system has been built based on two-phase high-frequency inverter using mechanical resonant frequency of the ultrasonic motor. The TMS320F243 digital signal processor (DSP) is adapted to ultrasonic motor drive system. The speed control of ultrasonic motor has been implemented...

In some austenitic stainless steel welds grains orientations cause deviation and splitting of the ultrasonic beam. It is especially true in the case of multipass welds when the remelting process after each pass causes complex solidification process. With the new model MINA (Modelling anisotropy from Notebook of Arc welding) we show that we are able to predict thoroughly grains orientations. Thi...

A simple method for imaging ultrasonic fields in clear media is introduced. A modulated laser source is used to project the ultrasonic field onto a CCD camera. By use of the source-synchronized lock-in detection scheme, 2D images of the amplitude and phase distributions can be determined simultaneously. This technique is experimentally demonstrated with a 1-MHz and a 3.5-MHz ultrasonic transduc...

In this article, embedded ultrasonic sensors were prepared using 1–3-type piezoelectric composite and piezoelectric ceramic as the piezoelectric elements, respectively. The frequency bandwidth of the novel embedded ultrasonic sensors was investigated. To obtain the relationship between the receiving ultrasonic velocity and compressive strength, as well as their response signals to crack damage,...

Electromagnetic ultrasonic transducer is the core component of the electromagnetic ultrasonic testing equipment. This paper establishes a three-dimensional model of the electromagnetic ultrasonic transducer used to generate Lamb wave, then by uniform design experiment and finite element analysis, the paper obtains the law between the eddy current density, the conductor width, length of the coil...

A novel microcomputer-based ultrasonic distance measurement system is presented. This study proposes an efficient algorithm which combines both the amplitude modulation (AM) and the phase modulation (PM) of the pulse-echo technique. The proposed system can reduce error caused by inertia delay and amplitude attenuation effect when using the AM and PM envelope square wave form (APESW). The APESW ...