The aim of this paper is to put forward a novel design nonlinear PID controller type based on carefully choosing gains enable reducing the settling time, minimizing overshoot and improving required control effort during functions read/write (R/W) head positioning servomechanism in hard disk drives. capable adjusting driving force, damping effect an integral action according position actual system output with respect desired output. This carried out by utilizing three actions which are tuned...

Water leaks from pipelines have large economic and ecological impacts. Minimizing water loss supply has favorable effects on the environment as well energy consumption. This paper aims to understand effect of geometry a leaking crack in pipe wall by examining fluid flow characteristics, namely pressure velocity distributions, inside pipe. Practical observations show that cause rupture influences cracks formed wall, impacting aspects such excessive pressure, corrosion. Knowledge...

This paper is concerned with the analysis of bending edge waves travelling in a thick Kirchhoff-type piezoelectric film resting on Winkler–Fuss foundation. The electromechanical coupling accounted for defining flexural rigidities to embrace and dielectric material constants. Dynamics solved analytically demonstrated numerically by assuming harmonic wave propagation. It observed that an increase voltage leads decrease critical velocity, while Winkler’s constant velocity.

Approximate numerical solutions are obtained for the vibration response of a functionally graded (FG) micro-scale beam entrapped within an axially-directed magnetic field using differential transformation method (DTM). Idealized as one-dimensional (1D) continuum with noticeable microstructural effect and thickness-directed material gradient, microbeam’s behavior is studied under range nonclassical boundary conditions. The immanent accounted through modified couple stress theory (MCST), while...

In this paper, guided ultrasonic wave propagation is analyzed in an elastic plate with sinusoidal surface corrugations. The corrugated area acts as a finite-length grating which corresponds to 1-D phononic crystal (PC). multiple-scale perturbation technique used derive coupled-mode equations describing the amplitudes of interacting modes. These are solved exactly for two-point boundary-value problem PC. study involves coupling incident symmetric Lamb S(0) reflected antisymmetric A(0)....

A fixed–fixed curved micro-beam resonator under the influence of harmonic electrostatic field is considered. Due to presence incompressible fluid between micro-beams and electrode, a squeeze-film damping affects dynamic behavior resonator. The combined effect geometry investigated for with concave convex geometries. reduced-order model obtained through application Galerkin discretization on coupled fluid–structure system composed nonlinear Euler–Bernoulli beam equation Burgdorfer’s...

In this paper, a model for transverse web vibration in roll-to-roll system is presented. Web axial tension and speed, decisive parameters the equation of motion that describes vibration, are rigorously obtained by considering two rolls-web coupled system’s dynamics, with motion. According to present analysis, idealized simply-supported boundary conditions, commonly used studies on vibrations axially moving structures not needed. Instead, mathematical comprised governing roll angular velocity...

In this paper, a finite difference approach is being presented as the most reliable technique to investigate non-linear transverse vibration of an axially moving beam. Firstly, Hamilton's principle used derive governing hyperbolic partial differential equation (HPDE) free vibration. Then along with state space method convert into system coupled first-order ordinary equations (ODE's). Comparison proposed model made both numerical and analytical models. It noted that in excellent agreement...

A structure with two periodicities can couple up to six modes under a case of simultaneous resonance resulting in stop-band interaction. The method multiple scales is employed analyze the modal coupling two-dimensional acoustic duct rigid periodically undulated walls as well an elastic plate having corrugated outerfaces, leading coupled-mode equations. comparison between three possible cases interaction are given terms power reflection coefficient spectrum function frequency. strength found...

An actuator comprised of a rigid substrate and two parallel clamped-clamped microbeams is modeled under the influence electrostatic loading. The problem considered context nonlinear Euler's mechanics, where actuating system described by coupled integrodifferential equations with relevant boundary conditions. Galerkin-based discretization utilized to obtain reduced-order model, which solved numerically. Actuators different gap sizes between electrode beams are investigated. obtained results...

The propagation of thermoelastic harmonic waves in bilaminated periodic waveguide is studied the context generalized theory thermoelasticity. A continuum mixture developed for traveling direction parallel to layering. As a result, problem transformed into quasi-one-dimensional one. resulting approximate expressions are found useful obtaining qualitative description response. symmetric mode an exact solution used check validity theory. Quasi-elastic and quasi-thermal modes investigated cases...

The vibration of an axially moving beam following a slightly curved path was studied. simply supported travelling on frictionless foundation with nonlinear elastic characteristics. main objective this work to investigate the effect curvature its vibration, and different parameters system’s dynamic response. These include axial speed, applied tension, stiffness supporting foundation. A Galerkin decomposition approach four-term truncation accuracy used realize mathematical model that describes...