【作者】 张志娟； 邹元杰； 关晓东；

【Author】 Zhijuan Zhang,Yuanjie Zou,Xiaodong Guan (China Academy of Space Technology)

【机构】 北京空间飞行器总体设计部；

【摘要】 折叠式太阳翼是最常用的为航天器提供电源的一类太阳翼。该类太阳翼通常包含一个连接架和数块帆板,发射阶段收拢入轨后展开。展开结束时刻太阳翼各铰链特别是根铰驱动机构(SADA)处会有较大的冲击载荷。冲击载荷超过SADA的承受限度,就会造成结构和机构破坏、太阳电池无法正常供电的恶劣后果。在地面开展真空环境中的展开锁定试验非常困难,因此有必要采用分析手段对锁定冲击载荷进行预计和评估。本文针对一类典型太阳翼,利用NASTRAN建立了连接架和3块太阳板的有限元模型,然后利用ADAMS软件建立了太阳翼展开锁定柔性多体分析模型。过去对锁定过程一般采用刚性连接代替有限元模型中铰链梁单元,然后用单自由度转动铰链连接各部件和建立锁定力矩的建模方法。本文研究了一种新的锁定过程建模方法,该方法能够考虑铰链的所有刚度特性。并基于该方法,研究了下列参数变化对锁定冲击载荷的影响:(a)采用Guyan缩聚法将有限元模型导入柔性多体系统模型的模态数;(b)仿真步长;(c)铰链刚度;(d)柔性体模态阻尼。通过分析可知计算时需选取足够多的模态以及足够小的仿真步长,还要采用较小模态阻尼以得到冲击载荷的保守设计值。同时当地面试验有多组刚度测试结果时,为了保证SADA可靠性,应该选取最大刚度试验值代入分析。研究表明本文采用的新的太阳翼展开锁定铰链建模方法能够得到准确的冲击载荷结果并易于实施。更多还原

【Abstract】 Fold-up solar array is widely used to provide power for spacecraft.A solar array usually contains a yoke and several panels,which are folded during launch and deployed in orbit. At the end of deployment,there are severe latch-up impact loads on hinges,especially on SADA (Solar Array Drive Assembly).If the impact loads on SADA exceed its permissible capability,it would result in mechanical or functional failure.Since it’s hard to carry on solar array deployment and latch-up test on the ground in a vacuum environment,it’s necessary to predict the in-orbit impact load accurately,which is critical to evaluation of the SADA design scheme. In this paper,a general deployment and latch-up analysis model is built for the typical solar array,which combines the finite element models including the yoke,and panels with NASTRAN and the multibody deployment and latch-up model with ADAMS.In the past,the revolution joints and the modified FE models with rigid multi-point constraints are applied to represent the hinges,which can only partly embody the dynamic behavior of hinges.In this paper,a new method is presented to build the hinge models,which introduce all the important stiffness and mass parameters of hinges.Then the effects of certain computation parameters on latch-up impact loads are investigated including:(a)the number of modes translated from FE model to multibody model with Guyan reduction method,(b) analysis step size,(c) stiffness of the hinge and (d) mode damping ratio. The results show that an adequate number of modes and a small step size should be considered in order to get a reasonable result,and that the smaller damping ratio is recommended to be applied in the computation in order to gain conservative design loads.Besides,if several hinge stiffness values are provided by the ground test,the biggest one should be used to get a conservative impact response.It is concluded that the new general deployment and latch-up analysis model for solar arrays presented in this paper could obtain accurate impact results and be easily applied.更多还原