被动输入过约束四面体可展天线机构动力学分析  

Dynamics of Passive-input Overconstrained Deployable Antenna Mechanisms Composed of 3RR-3RRR Tetrahedron Units

作　　者：刘文兰[1] 许允斗[1,2] 郭金伟[1] 姚建涛[1,2] 赵永生[1,2] LIU Wenlan;XU Yundou;GUO Jinwei;YAO Jiantao;ZHAO Yongsheng(Parallel Robot and Mechatronic System Laboratory of Hebei Province,Yanshan University,Qinhuangdao 066004;Key Laboratory of Advanced Forging&Stamping Technology and Science of Ministry of National Education,Yanshan University,Qinhuangdao 066004)

机构地区：[1]燕山大学河北省并联机器人与机电系统实验室,秦皇岛066004 [2]燕山大学先进锻压成型技术与科学教育部重点实验室,秦皇岛066004

出　　处：《机械工程学报》2020年第5期181-191,共11页Journal of Mechanical Engineering

基　　金：国家自然科学基金(51675458);河北省自然科学基金重点(E2017203335);河北省高等学校青年拔尖人才计划(BJ2017060)资助项目。

摘　　要：建立了一种由3RR-3RRR四面体单元组成的被动输入过约束可展天线机构的动力学模型,分析了驱动元件(扭簧)的数量、刚度、初始压缩量对机构展开运动的影响。基于3RR-3RRR四面体单元组成的可展机构的结构特点和空间坐标变换关系建立了机构展开/收拢过程中各构件质心位置与机构展开角之间的关系,得到了各构件的速度解析表达式。根据机构自由度性质,将机构展开/收拢过程中构件的运动分为平移运动、定轴转动、平面运动和复合运动四类。为便于建立3RR-3RRR四面体单元组成的被动输入过约束可展机构的动力学模型,进一步将构件的复合运动分解为平面运动和沿该平面法线方向的平移运动。基于拉格朗日法建立了单元可展机构3RR-3RRR和组合可展机构3(3RR-3RRR)-3RRR-3RRR的动力学模型,得到了机构中扭簧刚度与机构展开角之间的表达式,并讨论了扭簧刚度和数量对机构展开运动的影响。基于ADAMS仿真软件建立了3(3RR-3RRR)-3RRR-3RRR被动输入过约束可展机构的仿真模型,通过添加不同数量、不同刚度的扭簧对机构进行了动力学仿真分析,并讨论了扭簧初始压缩量对机构展开运动的影响,仿真结果验证了理论分析的正确性。研究结果可为由3RR-3RRR四面体单元组成的大型被动输入过约束可展天线机构的协调控制提供理论指导作用。The dynamic model of a passive-input overconstrained deployable antenna mechanism composed of 3 RR-3 RRR tetrahedron units is established, and the effects of the number, stiffness and initial compression angle of driving elements(i.e., torsion springs) on the motion of mechanism are analyzed. Based on the structural characteristics and spatial coordinate transformation formulas the relationships between the positions of the centroid of each component and the independent deployment angle of the mechanism are deduced, and then the analytical expressions of velocities of all components are obtained. The movements of all components are divided into translation motion, fixed-axis rotation, plane motion and compound motion according to the characteristic of the degree of freedom(DOF) of the mechanism. For the sake of dynamic analysis of the passive-input overconstrained mechanism, the composite motion of components is further decomposed into plane motion and translation motion along the normal direction of the plane. The dynamic models of the passive-input overconstrained deployable mechanism 3 RR-3 RRR and its combined mechanism 3(3 RR-3 RRR)-3 RRR-3 RRR are built by using Lagrange method. The relationships between the stiffness of torsion springs and the independent deployable angle of the mechanisms are obtained, and the influence of the stiffness and number of torsion springs on the deployable motion of the mechanisms is analyzed. The simulation model of 3(3 RR-3 RRR)-3 RRR-3 RRR mechanism is established by Adams software. The simulation is carried out by adding torsion springs with different numbers and stiffness. In addition, the effect of initial compression angle of torsion springs on the deployable motion of the mechanism is discussed. The simulation results verify the correctness of theoretical analyses. The results can provide theoretical guidance for the coordinated control of passive-input overconstrained deployable antenna mechanisms composed of 3 RR-3 RRR tetrahedron units.

关 键 词：过约束 可展机构 动力学 刚度 拉格朗日法 

分 类 号：V243[航空宇航科学与技术—飞行器设计] TH112[机械工程—机械设计及理论]