细长柔性空间结构几种动力学模型的比较  

A COMPARISON OF SEVERAL DYNAMIC MODELS FOR SLENDER FLEXIBLE SPACE STRUCTURE

作　　者：赵国威[1] 吴志刚[1,2] 

机构地区：[1]大连理工大学工业装备结构分析国家重点实验室,大连116024 [2]大连理工大学航空航天学院,大连116024

出　　处：《动力学与控制学报》2016年第2期122-130,共9页Journal of Dynamics and Control

基　　金：国家自然科学基金资助项目(11432010;11072044);高等学校博士学科点专项科研基金(20110041130001);教育部新世纪优秀人才支持计划(NCET-11-0054)~~

摘　　要：对于自由-自由边界的大型柔性梁式空间结构在轨搬运过程中,其大范围刚体运动和柔性振动会相互耦合,是一类典型的刚柔耦合动力学问题.建立相对准确的动力学模型是设计良好控制系统的前提,但现有文献在研究该问题时却采用了忽略刚柔耦合作用的动力学模型并依此设计控制器,因此有必要建立耦合模型,并探讨其与非耦合模型之间的区别和适用性.首先针对结构自身运动特点选择以瞬时质心为原点的浮动坐标系作为辅助坐标系,将结构两类不同的运动形式进行分解,并利用其产生的附加约束条件简化虚功表达式;其次选择Euler-Bernoulli梁变形形式描述结构变形并采用假设模态法对变形进行变量分离;基于虚功原理推导得到结构大范围运动的刚柔耦合动力学模型;通过仿真算例1对非耦合模型、零次近似模型和一次近似模型进行了对比,验证了非耦合模型的不合理性及零次近似简化模型的准确性和有效性;通过仿真算例2对零次近似简化模型和一次近似模型的对比,说明了二者的使用范围;仿真对比为后续的运动控制系统设计和振动抑制研究提供了依据.Dynamic modeling method of on-orbit maneuvering of free-free slender flexible space structures was studied. In literature,a dynamic model without rigid-flexible coupling terms was adopted for designing motion controller. Establishing a dynamic model with relatively accuracy is the premise of obtaining a well-designed motion controller,therefore,it is necessary to establish the coupling model and find the difference between them.A floating reference frame was chosen as local reference frame,whose origin is consistent with the center of mass.The assumed mode method was used for discretizing the deformation parameter. The rigid-flexible coupling dynamic equations of structure undergoing large overall plane motion were obtained based on the virtual work principle. Through several simulation examples,the difference between uncoupling equations and coupling equations was discussed,and the results show that the uncoupling model is not accurate enough and simple zeroorder model is more accurate and effective. The analysis provides an important basis for the subsequent motion controller design and vibration attenuation.

关 键 词：柔性空间结构 在轨搬运 浮动坐标系 刚柔耦合 自由-自由边界 

分 类 号：O313[理学—一般力学与力学基础]