US-Egypt Cooperative Research: On-Line Tonal Tuning of a Variable Inertia Vibration Absorber

Northern Illinois University, Dekalb IL

Investigators

Abstract

0108951 Fallahi Description: This award is to support a collaborative project by Dr. Behrooz Fallahi and Dr. Mohamed Seif, both in the Department of Mechanical Engineering, Northern Illinois University, Dekalb, Illinois, and Dr. Said Megahed, Mechanical Design and Production Department, Cairo University, Cairo, Egypt. They plan to study the dynamics and control of a new class of adaptive Tuned Vibration Absorber (TVA: variable effective inertia absorber). The approach has two facets: spectral analysis of the excitation and online tuning of the absorber. The spectral analysis reveals the frequency content of the excitation. The online tuning uses the frequency content of the excitation to reposition a moving mass for tonal vibration suppression. The analytical work, involving linearization of equations and study of its effect, will be supplemented by experimental study to assess the effectiveness of the proposed tonal tuning method. The novelty of the method is that the absorber tuning is done online for tonal vibration suppression, that moving a secondary mass changes absorber resonant frequency, and that the dynamic equation is derived with time dependent control parameter. Scope: The proposed technique may be widely implemented in industrial cases such as civic structures, airplane wings, submarine hulls, and helicopter cabins. The stability of the vibration suppression device is always guaranteed. The US and Egyptian collaborator have strong records of research and experience in mechanical dynamic systems, vibrations and control, and application to robotics and automating systems. The two sides complement each other, as Dr. Megahed is particularly experienced in modeling and simulation, while the US team is particularly strong in the planning and execution of the experiments and in the analysis of the data. The proposal meets the INT objective of supporting collaborative research in areas of mutual interest. This project is being supported under the US-Egypt Joint Fund Program, which provides grants to scientists and engineers in both countries to carry out these cooperative activities.