| Abstract [eng] |
This article belongs to the Special Issue “Ultrasonic Transducers and Related Apparatus and Applications”. Use of ultrasound is widely accepted in industry and research. Ultrasound is used for non-destructive testing (NDT), diagnostic imaging in medicine, flow velocity and material mechanical properties measurements. Ultrasonic actuators are popular in micro-scale positioning or mechanical processing. Transduction of the ultrasound still needs improvement: sensitivity, bandwidth and cost of the transducers receive the most efforts in research. The next most important part of any ultrasonic system is the signal technology. Research in signal technologies is aimed at: (i) transmission, reception and acquisition electronics, (ii) search for new signal types, (iii) signal processing techniques and instrumentation. This Special Issue was aimed to present the most recent developments in ultrasound transduction and signal technologies. A total of six papers are presented in this Special Issue. Ultrasound application in material processing is offering several advantages over the conventional technologies. In ultrasonic cutting, the vibration applied to a cutting tool reduces the required force, decreases the friction force and the stress on a workpiece, thus providing a uniform cross section of the cut. Hahn et al. [1] presented development and optimization of an ultrasonic horn that can be used for hard materials cutting. It was demonstrated that the cutting force was reduced to 30 % of the conventional requirement and the quality of cutting surface was improved when applied for silicon composite material slicing. Ultrasonic actuators offer high power-to-volume ratio, do not use magnetic materials and can provide down to nanometers resolution. Jurenas et al. [2] presented a novel ultrasonic motor design, capable of three degrees of freedom (3DoF). Motors with 3DoF can be used as a gyro stabilization platform, positioning other measurement instruments. The presented design was focused on miniaturization and high-power density. It contains a spherical rotor and two unimorph-type actuators. Rotor speed of 30 rpm was achieved at a 70 V driving signal. [...]. |
