Ultrasonic pulse-echo devices have shown utility for obstacle detection in numerous mobile robot research eflorts, as well as in commercial automatic guided vehicles (AGVs). A method for quickly obtaining multiple sonar range readings is presented. Thirty ultrasonic transducers are arranged in a ring and controlled by a computer. The system is predominantly composed of commercially available pa...

Air – coupled ultrasonic investigation possess a great potential for investigation of aerospace composite materials, because it avoids disadvantages caused by immersion or contact techniques. In the work the test sample of the GLARE3-3/2 composite material with artificial delamination type defect was investigated. Numerical and experimental investigations using focussed air – coupled ultrasonic...

This paper presents a microfluidic mixer that uses acoustic stirring created by ultrasonic waves. The ultrasound is introduced into the channel by integrated piezoelectric transducers. The transducers are made of a zinc oxide thin film, which is deposited on the bottom surface of a quartz substrate. The poly(dimethylsiloxane) channel is aligned to the transducers on the top surface of the subst...

An indication of the formability of metallic sheet is determined using a correlation between nondestructively measurable ultrasonic properties and a formability index. A calibration relation is initially established by measuring ultrasonic velocities at various angles to the rolling direction of sheet specimens with noncontacting electromagnetic acoustic transducers, calculating an ultrasonic c...

Time reversal is a very powerful method for focusing through complex and heterogeneous media and shows very promising results in biomedical applications. In this paper, we review some of the main applications investigated during the past decade. An iterative implementation of the time-reversal process allows tracking gallstones in real time during lithotripsy treatments. In this application dom...

Ultrasonic guided waves are used to detect the delamination between skin and honeycomb of a composite helicopter rotor blade. Theoretical work is carried out for guided waves in the trailing edge of a rotor blade, which is a multilayer composite skin/NOMEX half space structure. The dispersion relation is obtained with the global matrix method. Theoretically driven experiments are conducted on a...