Structural identification based on vibration data for flexible and rigid multibody system dynamics.

摘要

This study presents structural identification techniques for dynamic modeling and simulation of flexible and rigid multibody systems. The aim of this study is to develop, based on experimentally obtained vibration data, more practical and suitable dynamic models of flexible bodies in multibody systems. Special attention is given to structural identification for extraction of correct modal data from available vibration data. The measured vibration data may be either a complete or an incomplete set.; In modal dynamics, modal data are primary known quantities that must be obtained either experimentally or analytically. In a multibody system, a flexible body may be connected to other bodies by springs and/or kinematic joints. However, for vibration measurements, the flexible body may be constrained differently than its actual conditions in the multibody system. Therefore, in order to apply the experimentally obtained modal data to the dynamic model, the measured vibration data must be properly identified.; Although recent research on the subject of flexible multibody dynamics has experienced a tremendous growth, most work in modeling a flexible body is based on the finite element method, where its application is limited to positive definite (adequately supported) flexible bodies. On the other hand, the study of semidefinite flexible bodies in multibody systems is still at a rudimentary stage. This study is focused on structural identification of semi-definite flexible bodies for multibody dynamic modeling.