Session: MSNDC-04/VIB-09-03: Nonlinear Dynamics of Systems and Structures

Paper Number: 114952

114952 - Nonlinear Dynamics Simulation of the Contact Force in Planar Mechanism With Clearance 

A planar mechanism with three moving parts is connected to a cam. The mechanism is consisted from crank arm, connecting rod, flat-faced follower, polydyne cam, and two guides with clearance. The investigation of the dynamic simulation of the contact force between the cam and the follower is considered in the presence of crank arm and connecting rod mechanism. Nonlinear response of the contact force is simulated at different guide width of the follower and at different cam speeds. SolidWorks program is used in the calculation of contact force at different cam speeds and different guides’ widths. The nonlinear dynamics simulation of the planar mechanism is described using Lyapunov exponent parameter, Poincare’ map, Fast Fourier Transform, and phase-plane mapping. Local Lyapunov exponent is calculated using the MatLab code of the dynamic tool algorithm based on the values of time delay and embedding dimensions. The amplitude of Fast Fourier Transform is determined using power spectrum and autocorrelation analysis. Phase-plane diagram is drawn using the relationship between the contact force and its variation. The outcome of this paper is to detect the chaotic phenomenon in planar mechanism in the presence of crank arm and connecting rod based on the variation of the contact force against time between the cam and the follower. The periodic time of the follower displacement is decreased while the frequency has been increased with the increasing of cam speeds and with the increasing of guides’ widths. The intensity of the periodicity of the linear displacement is increased with the increasing of cam speeds and with the increasing of guides’ widths. The chaos motion of the follower is recognized when the local Lyapunov exponent is positive while the periodic motion of the follower has negative value of Lyapunov exponent parameter.

Presenting Author: Louay Yousuf San Diego State University

Presenting Author Biography: Louay S. Yousuf is a Visiting Assistant Professor at San Diego State University for one academic year in the Department of Mechanical Engineering. He received his Ph.D. from the University of Baghdad, Baghdad, Iraq and was a Postdoctoral Fellow at the Mechanical Engineering Department, University of Auburn, Alabama before joining San Diego State University. His research interests include non-linear dynamics of cam and follower, composite materials, finite element method, vibrations, and experimental stress analysis.

Contact Information: lalroomi@sdsu.edu; Phone: (334) 332-5771.

Authors:

Louay Yousuf San Diego State University