高陡度曲面光学元件的虚拟轴磁流变抛光  

Virtual axis magnetorheological finishing of high-steepness curved optical elements

作　　者：付志伟 周涛 张桂梅[1,2] 谢炳贤 苏星 黄文 海阔 FU Zhiwei;ZHOU Tao;ZHANG Guimei;XIE Bingxian;SU Xing;HUANG Wen;HAI Kuo(School of Aeronautical Manufacturing and Mechanical Engineering,Nanchang Hangkong University,Nanchang 330063,China;Sichuan Precision and Ultra-Precision Machining Engineering Technology Center,Chengdu 610200,China)

机构地区：[1]南昌航空大学航空制造与机械工程学院,江西南昌330063 [2]四川省精密超精密加工工程技术研究中心,四川成都610200

出　　处：《光学精密工程》2025年第5期751-762,共12页Optics and Precision Engineering

基　　金：国家重点研发计划资助项目(No.2022YFB3403402);“某装备光束系统关键器件超精密加工制造生产线”项目(No.J0017-2326-QT)。

摘　　要：为了克服传统抛光轮上置式磁流变抛光机床在加工高陡度曲面光学元件时的工艺限制,并解决现有虚拟轴技术仅适用于小角度范围的局限性,提出了一种抛光轮下置固定式机械轴与虚拟轴复合联动抛光技术。基于抛光轮下置式磁流变抛光机床的结构特点,采用Denavit-Hartenberg(DH)法建立了机床机械轴与虚拟轴复合联动抛光的后置处理模型,并通过几何法进行了理论验证。通过虚拟轴凹球面采斑实验和均抛一块口径为150 mm、曲率半径为150 mm的熔石英凹球面,验证了后置处理模型的准确性。最后,对一块口径为170 mm、曲率半径为158 mm、最大法向角为32.54°的熔石英凹球面进行抛光修形。实验结果表明,修形后裁边5 mm的工件面形PV值收敛至0.04λ,RMS值收敛至0.005λ。所提出的机械轴与虚拟轴复合联动抛光模型具有较高的准确性,且能够有效提高高精度、高陡度曲面光学元件的加工能力,为磁流变抛光技术在高陡度复杂曲面光学元件加工中的应用提供了重要参考。In response to the technological constraints of traditional magnetorheological finishing machines,which typically feature an upper-mounted polishing wheel and encounter difficulties in processing optical components with significant steepness,this study introduces a compound linkage polishing technology.This innovative approach integrates a fixed mechanical axis with a virtual axis and employs an undermounted fixed polishing wheel.Initially,a post-processing model for the compound linkage polishing of both the mechanical and virtual axes is established,informed by the structural characteristics of the undermounted fixed polishing wheel.The model is articulated using the Denavit-Hartenberg(DH)method and is subsequently validated through geometric analysis.The accuracy of the established post-processing model is further corroborated by conducting spot-picking experiments on a virtual shaft concave spherical surface and uniform polishing experiments on a fused silica concave spherical surface,both with a diameter of 150 mm and a radius of curvature of 150 mm.Ultimately,a concave spherical surface crafted from molten fused silica,with a diameter of 170 mm,a radius of curvature of 158 mm,and a maximum normal angle of 32.54°,is polished and refined.Experimental results indicate that the PV value of the workpiece surface,with a trimming of 5 mm,converges to 0.04λ,while the RMS value converges to 0.005λpost-modification.These findings highlight that the proposed combined polishing model of the mechanical and virtual axes provides high precision and significantly enhances the processing capabilities for high-precision,high-gradient curved optical elements.This research contributes valuable insights into the application of magnetorheological polishing technology in the fabrication of complex curved optical elements with high steepness.

关 键 词：磁流变抛光 高陡度曲面 虚拟轴 下置式 后置处理 

分 类 号：TH706[机械工程—仪器科学与技术]