This artcile is concerned with thermal buckling and thermal induced free vibration analyses of PCPs (perforated composite plates) with simply supported edges applying a mathematical model. The stiffness and density of PCP are defined locally using Heaviside distribution functions. The governing equations are derived based on CLPT. The present solution gives reasonable results in comparison with...

An aeroelastic model of a smart rotor system (which incorporates blade-mounted trailing-edge flap actuators and conventional root pitch actuation) is presented in linear time invariant state space form. The servo-flap deflections are modeled as producing incremental lift and moment variations, so that any linear aerodynamic actuator can be evaluated. This smart rotor model is used to conduct pa...

Accurate uncertainty modeling is crucial in robust vibration controller design. A novel uncertainty modeling technique that enhances the estimated H∞ norm of the model error based on the frequency response is developed in this paper. The major innovation is the use of the local rational method (LRM), a local parametric modeling method, to address the inter-grid error. Unlike classical frequency...

A defect-free rolling element bearing has a varying stiffness. The variation of stiffness depends on number of rolling elements, their configuration and cage frequency. The time-varying characteristics of the stiffness results in a parametric excitation. This may lead to instability which is manifested as high vibration levels. An FEM simulation is performed to evaluate stiffness in each config...

Vibrotactile rendering is one of the most popular means for improving the user interface of a mobile device, but the availability of related perceptual data that can aid vibrotactile effect design is not currently sufficient. The present paper reports data from a series of psychophysical studies designed to fill this gap. In Experiment I, we measured the absolute detection thresholds of sinusoi...

In this study, a semi analytical method for transverse and axial vibration of single-walled boron nitride nanotube (SWBNNT) under moving a nanoparticle is presented. The surrounding elastic medium as Pasternak foundation and surface stress effect are included in the formulations of the proposed model. Using Timoshenko beam theory (TBT), Hamilton’s principle and nonlocal piezoelasticity theory, ...

The dynamic responses of membrane are completely dependent on Pre-tensioned forces which are applied over a boundary of arbitrary curvilinear shape. In most practical cases, the dynamic responses of membrane structures are undesirable. Whilst they can be designed as vibration-based energy harvesters. In this paper a smart flat membrane sheet (SFMS) model for vibration-based energy harvester is ...

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 low quality factor (Q) of single-walled carbon nanotube (SWNT) resonators has limited their sensitivity in sensing application. To this end, we employ the technique of parametric amplification by modulating the spring constant of SWNT resonators at twice the resonant frequency and achieve 10 times Q enhancement. The highest Q obtained at room temperature is around 700, which is 3–4 times be...

Nonlinearity plays a critical role on the behavior of oscillators operating in the parametric resonance mode. Here, we study the effects of Effective Nonlinear Parameter, (effective cubic stiffness), γ3eff, on the behavior of parametric resonance in a micro electro mechanical oscillator. The value of γ3eff can be tuned by changing the amplitude of applied voltage. Varying the sign of γ3eff can ...