Single-Degree-of-Freedom Dynamic Vibration Absorber for Unknown System

Abstract

Vibration causes problems, and the technology of dynamic vibration absorber is always used to control it. So far, the technology is mature, but based on the known of modes, mass, stiffness, damping and other parameters of the vibration system. For an unknown system or complicated system, how to use this technology is what the paper mainly discusses. The dynamic vibration absorber of this paper is a single-degree-of-freedom, and only one direction is to be controlled. The evaluation function is the ratio between the system vibration response after adding dynamic vibration absorber and the original exciting force, which can reflect the effect of dynamic vibration absorber. After separating the unknown system and the dynamic vibration absorber, based on force analysis, we analyze them separately and deduce the calculating formula of the evaluation function. The order of parameters to be determined is mass, stiffness, and damping. Flow chart is presented on how to use the method. The method is validated by a known system of two degree-of-freedom vibration system. The main innovation of this paper is to propose a method of predicting the effect of adding a single-degree-of-freedom dynamic vibration absorber to an unknown system to control a certain direction. This method doesn’t need to consider the system damping factor. This paper extends the scope of technology application of dynamic vibration absorber.