含间隙的变拓扑多体系统动力学建模分析

Dynamic Modeling of Flexible Mechanical Systems with Clearance Connections via the Variable Topology Analysis

分析了含间隙多体系统的变拓扑结构特性 ,引入了基本约束和变结构约束概念。在动力学建模中将系统拓扑结构的变化表示为含间隙处约束关系的变化 ,即变结构约束的增加与删除 ,给出了拓扑结构切换点的识别方程 ,建立了含间隙多体系统动力学的广义模型。对典型含间隙系统进行了仿真研究 。

The beginning or the end of any of the contact events of a clearance connection causes the time-variant or unsteady topological behavior. Dynamics of mechanical systems with non-ideal joints is characterized by constraint equations and indicator ones. The occurrence of an impact event between two bodies in the joint is indicated by relative distance of the bodies under consideration, and by the contact forces additionally in the case of penetration. The indicator equations are obtained from the internal geometry of the connection, and the contact forces in the joint are modeled by elastic, damping and friction properties of the joint. The dynamic models are developed respectively by introducing general force functions for contact-separate mode of the clearance joints, and adding and/or deleting kinematic constraint equations for contact-impact-separate description. A typical flexible mechanical system is presented as a numerical example to validate the development presented in this paper.