Showing papers by "Dumitru I. Caruntu published in 2014"
TL;DR: In this paper, a comparison between the Reduced Order Model (ROM) method and the Method of Multiple Scales (MMS) for both small and large amplitudes is reported for parametric resonance of microelectromechanical cantilever resonators under soft damping, and soft alternating current (AC) electrostatic actuation to include fringing effect.
Abstract: This paper deals with parametric resonance of microelectromechanical (MEMS) cantilever resonators under soft damping, and soft alternating current (AC) electrostatic actuation to include fringing effect. A comparison between the Reduced Order Model (ROM) method and the Method of Multiple Scales (MMS) for both small and large amplitudes is reported. The actuation is parametric non-linear. It includes non-linear terms with periodic coefficients. The AC frequency is near resonator׳s natural frequency. The amplitude frequency response is investigated using ROM. Damping, voltage, and fringe effects on the response are also reported. It is showed that five terms ROM accurately predicts the behavior of the resonator at all amplitudes, while MMS is accurate only for small amplitudes.
52 citations
TL;DR: In this paper, the authors deal with electrostatically actuated carbon nanotube (CNT) cantilever over a parallel ground plate and investigate the system under soft AC near half natural frequency of the CNT and weak nonlinearities.
Abstract: This paper deals with electrostatically actuated carbon nanotube (CNT) cantilever over a parallel ground plate. Three forces act on the CNTs cantilever, namely electrostatic, van der Waals, and damping. The van der Waals force is significant for values of 50 nm or less of the gap between the CNT and the ground plate. As both forces electrostatic and van der Waals are nonlinear, and the CNTs electrostatic actuation is given by AC voltage, the CNT undergoes nonlinear parametric dynamics. The methods of multiple scales and reduced order model (ROM) are used to investigate the system under soft AC near half natural frequency of the CNT and weak nonlinearities. The frequency–amplitude response and damping, voltage, and van der Waals effects on the response are reported. It is showed that only five terms ROM predicts and accurately predicts the pull-in instability and the saddle-node bifurcation, respectively.
20 citations
TL;DR: In this paper, the authors investigated the nonlinear response of a microelectromechanical system (MEMS) cantilever resonator electrostatically actuated by applying a soft alternating current (AC) voltage and an even softer direct current (DC) voltage between the resonators and a parallel fixed ground plate.
Abstract: This paper investigates the nonlinear response of microelectromechanical system (MEMS) cantilever resonator electrostatically actuated by applying a soft alternating current (AC) voltage and an even softer direct current (DC) voltage between the resonators and a parallel fixed ground plate. The AC frequency is near natural frequency. This drives the resonator into nonlinear parametric resonance. The method of multiple scales (MMS) is used to solve the dimensionless differential equation of motion of the resonator and find the steady-state solutions. The reduced order model (ROM) method is used to validate the results obtained using MMS. The effect of the soft DC voltage (bias) component on the frequency response is reported. It is shown that the DC bias changes the subcritical Hopf bifurcation into a cyclic fold bifurcation and shifts the bifurcation point (where the system loses stability) to lower frequencies and larger amplitudes.
10 citations
22 Oct 2014
TL;DR: In this paper, the voltage-amplitude response of soft AC electrostatically actuated M/NEMS clamped circular plates is analyzed using the method of multiple scales (MMS).
Abstract: This paper investigates the voltage-amplitude response of soft AC electrostatically actuated M/NEMS clamped circular plates. AC frequency is near half natural frequency of the plate. This results in primary resonance. The system is analytically modeled using the Method of Multiple Scales (MMS). The system is assumed weakly nonlinear. The behavior of the system including pull-in instability as the AC voltage is swept up and down while the excitation frequency is constant is reported. The effects of detuning frequency, damping, Casimir force, and van der Waals force are reported as well.Copyright © 2014 by ASME
2 citations
14 Nov 2014
TL;DR: In this article, the effects of nonlinearities of the system including pull-in instability on the voltage-amplitude response of clamped circular plates were investigated, and the effect of detuning frequency, damping, Casimir force, and van der Waals force on voltage response was reported.
Abstract: This paper utilizes Reduced Order Model (ROM) method to investigate the voltage-amplitude response of electrostatically actuated M/NEMS clamped circular plates. Soft AC voltage at frequency near half natural frequency of the plate is used. This results in primary resonance of the system. The effects of nonlinearities of the system including pull-in instability on the voltage-amplitude response are investigated. Namely, the effects of detuning frequency, damping, Casimir force, and van der Waals force on the voltage response of clamped circular plates are reported. Casimir and van der Waals forces are found to have significant effects on the response of clamped circular plates and must be considered to accurately model and predict the behavior of the system.Copyright © 2014 by ASME