刚柔耦合系统动力学建模及分析

Modeling and Analysis of a Coupled Rigid- Flexible System

准确预测经历大范围刚体运动和弹性变形的柔性体的行为,是当前柔性多体系统动力学领域关注的主要课题· 基于线性理论的传统方法由于无法计及动力刚化效应,导致在许多实际应用中得到错误的结果· 本文从离心力势场的概念出发,应用Hamilton原理建立了具有动力刚化效应的刚柔耦合系统的运动方程,证明了该方程解的周期性,并采用了Frobenius方法给出了其精确解的一般形式· 通过算例分析了刚体运动对弹性运动的模态和频率的影响·

Correct predictions of the behavior of flexible bodies undergoing large rigid_body motions and small elastic vibrations is a subject of major concern in the field of flexible multibody system dynamics. Because of failing to account for the effects of dynamic stiffening, conventional methods based on the linear theories can lead to erroneous results in many practical applications. In this paper, the idea of “centrifugal potential field”,which induced by large overall rotation is introduced, and the motion equation of a coupled rigid_flexible system by employing Hamilton's principle is established. Based on this equation, first it is proved that the elastic motion of the system has periodic property, then by using Frobenius' method its exact solution is obtained. The influences of large overall rigid motion on the elastic vibration mode shape and frequency are analysed through the numerical examples.