Predicting the Attenuation Characteristics of a Microvibration Damper for Automobile Bodies using Transfer-function Synthesis

摘要

A test damper developed to suppress the micro-vibrations of automobile bodies can produce a velocity-independent and nearly constant high damping force even at very small speeds. To select the optimum damping force for an arbitrary vehicle, it is necessary to establish a method for predicting the vehicle vibrations when the damper is installed, and this requires a physical model of the damper itself. A previous report elucidated the mechanism by which the damping force is generated and a linearization method is described. In the present report, a method is proposed for estimating the vibration response; the vibration of the vehicle body when the target linear damper is installed is estimated using only the vibration response; the transfer functions among the input, evaluation, and coupling points on the vehicle body; and the transfer function of the target damper itself. The feasibility of the proposed method is examined using finite-element simulation of a mock-up frame and a test damper. From the results, the vibration response of the mock-up frame with the test damper estimated with the proposed method and that calculated by direct analysis match well. Furthermore, application to an actual vehicle experiment is considered by estimating the response to a multi-directional and multi-point input.