光学学报, 2017, 37 (10): 1001003, 网络出版: 2018-09-07
变形镜的结构参数对其疲劳寿命的影响 下载: 788次
Influence of Structural Parameters of Deformable Mirror on Its Fatigue Life
自适应光学 变形镜 疲劳寿命 有限元分析 结构参数 交连值 adaptive optics deformable mirror fatigue life finite element analysis structural parameters coupling coefficient
摘要
在自适应波前校正过程中,变形镜(DM)受驱动器循环机械驱动作用会产生疲劳累积损伤。利用DM的影响函数和最小二乘法对波前校正过程进行模拟,采用有限元方法分析了DM在波前校正过程中的应力分布,并结合Miner疲劳累积损伤理论,计算了DM的疲劳寿命。在此基础上,重点讨论了DM结构参数对影响函数和DM疲劳寿命的影响。研究结果表明,对于给定的畸变波前,当DM极头数相同时,极头采用三角形排布方式时DM的交连值最小,疲劳寿命最长;极头采用正方形排布方式时DM的交连值最大,疲劳寿命最短。此外,当极头间距增大时,DM交连值会随之减小,致使DM的疲劳寿命变长。当极头间距相同时,增大极头半径和缩短极头长度会使DM的交连值变小,DM的疲劳寿命也会变短。极头间距变化对DM疲劳寿命的影响程度大于极头半径和长度;当极头间距一定时,不同的排布方式对应的极头数目不同,DM的极头数越多,疲劳寿命就越短。
Abstract
The cumulative fatigue damage of deformable mirrors (DMs) is generated due to the action of the circular mechanical drive of the actuators in the process of adaptive wavefront correction. The wavefront correction process of the DM has been simulated by the least squares method and the influence function of the DM, and the corresponding stress distribution of the DM in the wavefront correction process has also been analyzed by the finite element method. Additionally, the fatigue life of the DM has further been calculated with the Miner cumulative fatigue damage theory. On this basis, the influences of the structural parameters of the DM on the influence function and the fatigue life of the DM have been discussed. The results show that the coupling coefficient of the DM is minimal and the fatigue life is the longest when the poles are distributed in the triangular arrangement for the given distorted wavefront and the equal number of poles of the DM. However, the coupling coefficient of the DM is maximal and the fatigue life is the shortest when the poles are distributed in the square arrangement. Furthermore, the coupling coefficient of the DM decreases with the increasing pole spacing, resulting in the increasing fatigue life of the DM. Meanwhile, the coupling coefficient and the fatigue life of the DM decrease with the increasing pole radius and the decreasing pole length when the pole spacing is fixed. On the whole, the influence of the pole spacing on the fatigue life of the DM is more significant than that of the pole radius and length. Furthermore, for the given pole spacing, the number of the poles varies with pole distribution manners and the fatigue life of the DM decreases with the increasing number of poles.
罗帅, 陈丽霞, 张彬. 变形镜的结构参数对其疲劳寿命的影响[J]. 光学学报, 2017, 37(10): 1001003. Shuai Luo, Lixia Chen, Bin Zhang. Influence of Structural Parameters of Deformable Mirror on Its Fatigue Life[J]. Acta Optica Sinica, 2017, 37(10): 1001003.