The vibration signals of rolling bearings are often nonlinear and non-stationary. Multiscale entropy (MSE) has been widely applied to measure the complexity of nonlinear mechanical vibration signals, however, at present only the single channel vibration signals are used for fault diagnosis by many scholars. In this paper multiscale entropy in multivariate framework, i.e., multivariate multiscal...

This paper is concerned with a new fully adaptive control scheme for vibration isolation using a semi-active MR damper installed between ground and first floor, which is composed of two adaptive controllers. One is an adaptive inverse controller which can give necessary input voltage to MR damper so as to generate specified reference damping force to be acted on a controlled structure. The inpu...

In this study, nonlocal nonlinear instability and the vibration of a double carbon nanotube (CNT) system have been investigated. The Visco-Pasternak model is used to simulate the elastic medium between nanotubes, on which the effect of the spring, shear and damping of the elastic medium is considered. Both of the CNTs convey a viscose fluid and a uniform longitudinal magnetic field is applied t...

The paper a nonlinear model of bolt joints structure in vibration environment is built, including the friction, contact and so on complex nonlinear factors. Structure Intensity (SI) of it is calculated by Finite Element Method (FEM) as an approach for the state identification of bolts joints structure in vibration environment. The plots of the structure intensity vector under different tighteni...

Emily Stone Department of Mathematical Sciences, The University of Montana, Missoula, MT 59812 U.S.A. Abstract In this paper we present stability analysis of a nonlinear model for chatter vibration in a drilling operation. The results build our previous work [1, 2], where the model was developed and the nonlinear stability of the vibration modes as cutting width is varied was presented. Here we...

This paper deals with the nonlinear models of regenerative chatter on machine tools. The limitations and actual problems of the existing theory are summarized. These cause difficulties in industrial applications, like in the design of optimum technological parameters, adaptive control and/or vibration-suppression strategies. An industrial machine-tool vibration case is analysed experimentally a...

Parametric amplification, resulting from intentionally varying a parameter in a resonator at twice its resonant frequency, has been successfully employed to increase the sensitivity of many micro- and nano-scale sensors. Here, we introduce the concept of self-induced parametric amplification, which arises naturally from nonlinear elastic coupling between the degenerate vibration modes in a micr...

A recent study showed that fingertip pads' tactile sensation can improve by applying imperceptible white-noise vibration to the skin at the wrist or dorsum of the hand in stroke patients. This study further examined this behavior by investigating the effect of both imperceptible and perceptible white-noise vibration applied to different locations within the distal upper extremity on the fingert...