大范围运动刚柔耦合系统动力学建模与仿真

Dynamic modeling and simulation for the rigid-flexible coupling system with large overall motion

以往对刚柔耦合系统的控制研究多是基于传统零次近似动力学模型,当系统存在大范围运动时,零次近似动力学模型已不能正确揭示动力学行为。从连续介质力学的基本原理出发,在变形位移的描述中计及二次耦合项,同时忽略轴向拉伸量,得到更符合实际控制需要的简化一次近似动力学模型。仿真结果表明,该模型正确预示了系统的动力学行为;与传统一次近似耦合动力学模型相比,以更简单的形式引入动力刚化现象,是一种能够用于实际控制系统设计的高效、高精度的一次近似刚柔耦合动力学模型。

In the studies of active control of rigid-flexible coupling system,the traditional zero-order approximation dynamic models are usually used.However,when the rigid-flexible coupling system undergoes a large overall motion,those models can not reproduce the real dynamics behavior of system.A first-order approximation dynamic model is therefore proposed in this paper based on mechanics of continuous media.The second-order coupling terms of deformation are included in the longitudinal deformation while neglecting the axial extensional deformation of the central axis to get a simplified first-order dynamic model suitable for use in control design.The numerical simulation results show that the proposed model can predict the dynamics of the system accurately,with correct account for dynamic stiffening in a simple form,and can be used in practical engineering designs of control with high efficiency and precision.