Several experiments have been performed to investigate the mechanical vibrations associated with trachea and larynx when Italian vowels are emitted. The mechanical measurements have been made by using two laser Doppler vibrometers (based on the well-known not-invasive optical measurement technique) coupled with the acoustic field measured by high-quality certified microphones. The recorded sign...

Near-field optical techniques exploit light-matter interactions at small length scales for mechanical sensing and actuation of nanomechanical structures. Here, we study the optical interaction between two mechanical oscillators--a plasmonic nanofocusing probe-tip supported by a low frequency cantilever, and a high frequency nanomechanical resonator--and leverage their interaction for local dete...

This paper presents a vibration suppression approach for precision positioning mechanisms including harmonic drive gearings (HDGs), using a variable notch filter to suppress mechanical vibrations due to angular transmission errors (ATEs) in HDGs. Mechanisms with HDGs excite resonant vibrations, especially in the condition that the frequency of synchronous components of ATE correspond to the cri...

Conventional strategies to measure mechanical vibrations from remote distance are based on Laser-Doppler-vibrometry (LDV). This technique is only rarely used in practical structural health monitoring (SHM) applications, due to the high costs of these devices. Radar technology represents a promising new approach towards in-situ SHM-scenarios with permanently installed sensors, because of the low...

A technique to locally generate mechanical vibrations in freestanding graphene using scanning tunneling microscopy (STM) is presented. The frequency of the mechanical vibrations is tuned over nearly four decades and is centered around 10 Hz. The amplitude of the vibrations also changes over nearly three decades centered on 1 nm. The oscillating motion is generated in two ways: first, by scannin...

We consider dc-electronic transport through a nanowire suspended between two normal-metal leads in the presence of an external magnetic field. We show the very mechanism through which such a system, whose stationary current-voltage characteristic is essentially characterized by positive differential conductance, becomes unstable with respect to an onset of self-excited oscillations in electrica...

We consider dc-electronic transport through a nanowire suspended between normal- and spin-polarized metal leads in the presence of an external magnetic field. We show that magnetomotive coupling between the electrical current through the nanowire and vibrations of the wire may result in self-excitation of mechanical vibrations. The self-excitation mechanism is based on correlations between the ...

ABSTRACT: This paper presents scheme for the speed control of electrical drive when the mechanical system shows low damped mechanical resonance. This situation happens when a comparatively long shaft drives the load. In this case the presence of torsion vibrations can cause wear of gear boxes and quality deterioration of the working process and of resulting products. To damp torsion vibrations ...

In this paper, we study the unobserved vibrations of the head in hard disk drives which may lead to destruction of user data. We show that the acceleration input excites the mechanical resonance near the sampling frequency of the hold in the settling characteristics after the track-seeking control. We also show that the degree to which these oscillations are unobservable depends on the sampling...