光学 精密工程, 2009, 17 (1): 1, 网络出版: 2009-10-09
基于PZT的非球面能动抛光盘的变形优化
Optimization control of PZT actuated deformable aspheric polishing lap
非球面镜 非球面能动抛光盘 迟滞效应 径向基神经网络 aspheric mirror deformable aspheric polishing lap hysteresis effect Radial Basis Function(RBF) neural network
摘要
基于PZT压电陶瓷驱动器的非球面能动抛光盘,能够在PZT驱动器的作用下改变面形,用于中小口径非球面镜加工。研制了一个口径100 mm、含19个PZT驱动器的非球面能动抛光盘,用于口径为350 mm、k=-1.112 155、顶点半径为840 mm的双曲面镜的加工实验。为研究PZT压电陶瓷驱动器迟滞效应对非球面能动抛光盘输出面形的影响,实测各PZT压电陶瓷驱动器的电压位移特性曲线,用基于径向基函数的神经网络算法建立了各PZT压电陶瓷驱动器位移输出特性的数学模型并实施补偿,实测了各PZT压电陶瓷驱动器迟滞补偿前后的位移输出值。最后,利用有限元分析方法,得到了迟滞补偿前后非球面能动抛光盘的输出面形RMS以及剩余残差RMS分别为1.910 μm和0.342 μm。通过补偿各PZT压电陶瓷驱动器的迟滞效应,非球面能动抛光盘输出面形精度得到了提高,剩余残差RMS减少了82%。
Abstract
The deformable aspheric polishing lap based on Piezoelectric(PZT) actuator can change the lap surface continuously to fit the surface of middle aperture aspheric optical mirrors at any location. In this paper,a 100 mm diameter and deformable aspheric polishing lap consisting of 19 PZT actuators was designed and manufactured to polish a Φ350 mm hyperboloid mirror in k=-1.112 155, R=840 mm. In order to analyze the influence of PZT actuator hysteresis on surface error, the output characteristic of each PZT actuator was measured and the mathematical model of displacement output of each PZT actuator was established by means of Radial Basis Function(RBF) neural network. By finite element method, the surface errors of the deformable aspheric polishing lap were calculated before and after PZT actuator hysteresis compensation. The results show that the surface residual error and RMS are 1.910 μm and 0.342 μm respectively. By PZT actuator hysteresis compensation, the surface error of the deformable aspheric polishing lap reduces by 82%.
胡自强, 凌宁, 潘君骅, 饶长辉, 姜文汉. 基于PZT的非球面能动抛光盘的变形优化[J]. 光学 精密工程, 2009, 17(1): 1. HU Ziqiang, LING Ning, PAN Junhua, RAO Changhui, JIANG Wenhan. Optimization control of PZT actuated deformable aspheric polishing lap[J]. Optics and Precision Engineering, 2009, 17(1): 1.