多体系统的通用程序SNERM

本文介绍基于子系统牛顿欧拉递推法编制的可进行多体系统运动学、动力学分析的通用程序SNERM,该程序以解机器人链系统为主程序块,通过增加各子程序块从而可处理系统中含有多自由度铰、含有运动激励、参考体具有一般运动、具有复杂的拓朴结构的复杂多体系统的动力学问题。并包含奇异值分解(SVD)子程序块,故可用SVD缩并法解约束多体系统动力学及解具有冗自由度系统运动学问题,并采用递推及程式化计算公式,适合工程应用及具有较高的计算效率,可广泛应用于航天器、机器人、车辆、机构等多体系统运动学动力学分析。文中对子系统牛顿欧拉递推法的特点作了简述,并对递推及程式化计算公式作了归纳。最后给出了两个分别是参考体具有转动及非树机构动力学分析算例。说明该程序应用方便,工程实用,可扩展性好,通用性强且计算正确。

A General Purpose Computer Program SNERM for Multibody Systems

In this paper, a general purpose computer program SNERM based on the Subsystem Newton-Euler Recursive Method for both the kinematics and dynamics of multibody systems, is introduced. The SNERM program is constructed by a main module for dealing with the dynamics of the manipulator chain structure and a series of subprogram modules for dealing with the dynamics of complicated systems with joints of multidegrees of freedom, with kinematic excitations, with reference body motions and with complicated topological structure.A Singular Value Decomposition (SVD) subprogram module is enclosed, so the SVD reductive method for the dynamics of constrained multibody systems can be applied and the Kinematics of the system with redundancy can be solved. The SNERM program, which is efficient and suitable for engineerirg applications, has a series of recursive and formulized formatting computations. It can be expansively applied in the kinematics and dynamics of general multibody systems, such as the spacecraft, the robots, the vehicles and the mechanisms etc. The characteristics of the Subsystem Newton-Euler Recursive Method is introduced briefly and a series of recursive and formulized formatting equations are presented. Two numerical examples are introduced. One is for the dynamics of the mechanism for a reference body with rotation, and the other is for the dynamics of a system with closed loop structure. It is shown that the SNERM program has good expansibility and accuracy and may be widely used.